1
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Jaapar FN, Parmin NA, Halim NHA, Hashim U, Gopinath SCB, Halim FS, Uda MNA, Afzan A, Nor NM, Razak KA. Micro-interdigitated electrodes genosensor based on Au-deposited nanoparticles for early detection of cervical cancer. Int J Biol Macromol 2023; 253:126745. [PMID: 37689297 DOI: 10.1016/j.ijbiomac.2023.126745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 08/22/2023] [Accepted: 08/27/2023] [Indexed: 09/11/2023]
Abstract
Genosensor-based electrodes mediated with nanoparticles (NPs) have tremendously developed in medical diagnosis. Herein, we report a facile, rapid, low cost and highly sensitive biosensing strategy for early detection of HPV 18 using gold-nanoparticles (AuNPs) deposited on micro-IDEs. This study represents surface charge transduction of micro-interdigitated electrodes (micro-IDE) alumina insulated with silica, independent and mini genosensor modified with colloidal gold NPs (AuNPs), and determination of gene hybridization for early detection of cervical cancer. The surface of AuNPs deposited micro-IDE functionalized with optimized 3-aminopropyl-triethoxysilane (APTES) followed by hybridization with deoxyribonucleic acid (DNA) virus to develop DNA genosensor. The results of ssDNA hybridization with the ssDNA target of human papillomavirus (HPV) 18 have affirmed that micro-IDE functionalized with colloidal AuNPs resulted in the lowest detection at 0.529 aM. Based on coefficient regression, micro-IDE functionalized with AuNPs produces better results in the sensitivity test (R2 = 0.99793) than unfunctionalized micro-IDE.
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Affiliation(s)
- F Nadhirah Jaapar
- Institute of Nano Electronic Engineering, Universiti Malaysia Perlis, 01000 Kangar, Perlis, Malaysia
| | - N A Parmin
- Institute of Nano Electronic Engineering, Universiti Malaysia Perlis, 01000 Kangar, Perlis, Malaysia.
| | - N Hamidah A Halim
- Institute of Nano Electronic Engineering, Universiti Malaysia Perlis, 01000 Kangar, Perlis, Malaysia
| | - Uda Hashim
- Institute of Nano Electronic Engineering, Universiti Malaysia Perlis, 01000 Kangar, Perlis, Malaysia; Faculty of Chemical Engineering Technology, Universiti Malaysia Perlis, 02600 Arau, Perlis, Malaysia
| | - Subash C B Gopinath
- Institute of Nano Electronic Engineering, Universiti Malaysia Perlis, 01000 Kangar, Perlis, Malaysia; Institute of Microengineering and Nanoelectronics, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia; Micro System Technology, Centre of Excellence (CoE), Universiti Malaysia Perlis (UniMAP), Pauh Campus, 02600 Arau, Perlis, Malaysia; Department of Computer Science and Engineering, Faculty of Science and Information Technology, Daffodil International University, Daffodil Smart City, Birulia, Savar, Dhaka 1216, Bangladesh
| | - F Syakirah Halim
- Institute of Nano Electronic Engineering, Universiti Malaysia Perlis, 01000 Kangar, Perlis, Malaysia
| | - M N A Uda
- Institute of Nano Electronic Engineering, Universiti Malaysia Perlis, 01000 Kangar, Perlis, Malaysia
| | - Amilia Afzan
- Department of Obstetrics and Gynaecology (O&G), Faculty of Medicine & Health Sciences, Universiti Putra Malaysia, 43400, UPM, Serdang, Selangor
| | - N Mohamad Nor
- School of Materials & Mineral Resources Engineering, Universiti Sains Malaysia, 14300 Nibong Tebal, Pulau Pinang, Malaysia
| | - Khairunisak Abdul Razak
- School of Materials & Mineral Resources Engineering, Universiti Sains Malaysia, 14300 Nibong Tebal, Pulau Pinang, Malaysia; NanoBiotechnology Research and Innovation (NanoBRI), Institute for Research in Molecular Medicine, Universiti Sains Malaysia, 11800 Penang, Malaysia
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2
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Mohamad Nor N, Nasrul SN, Zakaria ND, Abdul Razak K. Simultaneous Sensing of Cd(II), Pb(II), and Cu(II) Using Gold Nanoparticle-Modified APTES-Functionalized Indium Tin Oxide Electrode: Effect of APTES Concentration. ACS Omega 2023; 8:16587-16599. [PMID: 37214679 PMCID: PMC10193388 DOI: 10.1021/acsomega.2c07085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Accepted: 04/20/2023] [Indexed: 05/24/2023]
Abstract
In this work, indium tin oxide (ITO) electrodes were functionalized with varying 3-aminopropyltriethoxysilane (APTES) concentration percentages (0.5, 0.75, 1.0, and 2.0 wt %) to obtain the optimum conditions for the assembly of the as-synthesized gold nanoparticles (AuNPs). The AuNP coverage, wettability, and electrochemical performance of the modified electrodes were evaluated. The AuNP/0.75% APTES-ITO-modified electrode exhibited uniform coverage of AuNPs and high electrochemical performance for the simultaneous detection of Cd(II), Pb(II), and Cu(II) ions. Under the optimum conditions, the AuNP/0.75% APTES-ITO-modified electrode showed a linear detection range of 5-120 ppb and limit of detection of 0.73, 0.90, and 0.49 ppb for the simultaneous detection of Cd(II), Pb(II), and Cu(II) ions, respectively, via square wave anodic stripping voltammetry. The modified electrode demonstrated good anti-interference toward other heavy metal ions, good reproducibility, and suitability for application in environmental sample analysis.
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Affiliation(s)
- Noorhashimah Mohamad Nor
- School
of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, 14300 Nibong Tebal, Pulau Pinang, Malaysia
| | - Siti Nasirah Nasrul
- School
of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, 14300 Nibong Tebal, Pulau Pinang, Malaysia
| | - Nor Dyana Zakaria
- NanoBiotechnology
Research & Innovation (NanoBRI), INFORMM,
Universiti Sains Malaysia, 11800 Gelugor, Pulau Pinang, Malaysia
| | - Khairunisak Abdul Razak
- School
of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, 14300 Nibong Tebal, Pulau Pinang, Malaysia
- NanoBiotechnology
Research & Innovation (NanoBRI), INFORMM,
Universiti Sains Malaysia, 11800 Gelugor, Pulau Pinang, Malaysia
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3
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Zakaria ND, Hamzah HH, Salih IL, Balakrishnan V, Abdul Razak K. A Review of Detection Methods for Vancomycin-Resistant Enterococci (VRE) Genes: From Conventional Approaches to Potentially Electrochemical DNA Biosensors. Biosensors (Basel) 2023; 13:294. [PMID: 36832060 PMCID: PMC9954664 DOI: 10.3390/bios13020294] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 01/24/2023] [Accepted: 01/29/2023] [Indexed: 06/18/2023]
Abstract
Vancomycin-resistant Enterococci (VRE) genes are bacteria strains generated from Gram-positive bacteria and resistant to one of the glycopeptides antibiotics, commonly, vancomycin. VRE genes have been identified worldwide and exhibit considerable phenotypic and genotypic variations. There are six identified phenotypes of vancomycin-resistant genes: VanA, VanB, VanC, VanD, VanE, and VanG. The VanA and VanB strains are often found in the clinical laboratory because they are very resistant to vancomycin. VanA bacteria can pose significant issues for hospitalized patients due to their ability to spread to other Gram-positive infections, which changes their genetic material to increase their resistance to the antibiotics used during treatment. This review summarizes the established methods for detecting VRE strains utilizing traditional, immunoassay, and molecular approaches and then focuses on potential electrochemical DNA biosensors to be developed. However, from the literature search, no information was reported on developing electrochemical biosensors for detecting VRE genes; only the electrochemical detection of vancomycin-susceptible bacteria was reported. Thus, strategies to create robust, selective, and miniaturized electrochemical DNA biosensor platforms to detect VRE genes are also discussed.
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Affiliation(s)
- Nor Dyana Zakaria
- Nanobiotechnology Research and Innovation (NanoBRI), Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Gelugor 11800, Penang, Malaysia
| | - Hairul Hisham Hamzah
- School of Chemical Sciences, Universiti Sains Malaysia, Gelugor 11800, Penang, Malaysia
| | - Ibrahim Luqman Salih
- School of Chemical Sciences, Universiti Sains Malaysia, Gelugor 11800, Penang, Malaysia
| | - Venugopal Balakrishnan
- Nanobiotechnology Research and Innovation (NanoBRI), Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Gelugor 11800, Penang, Malaysia
| | - Khairunisak Abdul Razak
- Nanobiotechnology Research and Innovation (NanoBRI), Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Gelugor 11800, Penang, Malaysia
- School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, Nibong Tebal 14300, Penang, Malaysia
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4
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Mohamad Nor N, Ridhuan NS, Abdul Razak K. Progress of Enzymatic and Non-Enzymatic Electrochemical Glucose Biosensor Based on Nanomaterial-Modified Electrode. Biosensors (Basel) 2022; 12:bios12121136. [PMID: 36551103 PMCID: PMC9775494 DOI: 10.3390/bios12121136] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 11/28/2022] [Accepted: 12/02/2022] [Indexed: 05/09/2023]
Abstract
This review covers the progress of nanomaterial-modified electrodes for enzymatic and non-enzymatic glucose biosensors. Fundamental insights into glucose biosensor components and the crucial factors controlling the electrochemical performance of glucose biosensors are discussed in detail. The metal, metal oxide, and hybrid/composite nanomaterial fabrication strategies for the modification of electrodes, mechanism of detection, and significance of the nanomaterials toward the electrochemical performance of enzymatic and non-enzymatic glucose biosensors are compared and comprehensively reviewed. This review aims to provide readers with an overview and underlying concept of producing a reliable, stable, cost-effective, and excellent electrochemical performance of a glucose biosensor.
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Affiliation(s)
- Noorhashimah Mohamad Nor
- School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, Nibong Tebal 14300, Pulau Pinang, Malaysia
| | - Nur Syafinaz Ridhuan
- School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, Nibong Tebal 14300, Pulau Pinang, Malaysia
| | - Khairunisak Abdul Razak
- School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, Nibong Tebal 14300, Pulau Pinang, Malaysia
- NanoBiotechnology Research & Innovation (NanoBRI), Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Gelugor 11800, Pulau Pinang, Malaysia
- Correspondence:
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5
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Saidin S, Yunus MH, Zakaria ND, Razak KA, Huat LB, Othman N, Noordin R. Retraction Note: Production of recombinant Entamoeba histolyticapyruvate phosphate dikinase and its application in a lateral flow dipstick test for amoebic liver abscess. BMC Infect Dis 2022; 22:729. [PMID: 36076156 PMCID: PMC9461230 DOI: 10.1186/s12879-022-07708-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
- Syazwan Saidin
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, 11800, Penang, Malaysia
| | - Muhammad Hafiznur Yunus
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, 11800, Penang, Malaysia
| | - Nor Dyana Zakaria
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, 11800, Penang, Malaysia
| | - Khairunisak Abdul Razak
- School of Materials and Mineral Resources Engineering, Engineering Campus, Universiti Sains Malaysia, Nibong Tebal, 14300, Penang, Malaysia.,NanoBiotechnology Research and Innovation (NanoBRI), Institute for Research in Molecular Medicine, Universiti Sains Malaysia, 11800, Penang, Malaysia
| | - Lim Boon Huat
- School of Health Sciences, Universiti Sains Malaysia, Kubang Kerian, 16150, Kelantan, Malaysia
| | - Nurulhasanah Othman
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, 11800, Penang, Malaysia
| | - Rahmah Noordin
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, 11800, Penang, Malaysia.
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6
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Sisin NNT, Mat NFC, Rashid RA, Dollah N, Razak KA, Geso M, Algethami M, Rahman WN. Natural Baicalein-Rich Fraction as Radiosensitizer in Combination with Bismuth Oxide Nanoparticles and Cisplatin for Clinical Radiotherapy. Int J Nanomedicine 2022; 17:3853-3874. [PMID: 36081572 PMCID: PMC9448000 DOI: 10.2147/ijn.s370478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 06/19/2022] [Indexed: 12/24/2022] Open
Abstract
Purpose Methods Results Conclusion
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Affiliation(s)
| | - Nor Fazila Che Mat
- School of Health Sciences, Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia
| | | | - Norhayati Dollah
- Department of Nuclear Medicine, Radiotherapy and Oncology, Hospital Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia
| | - Khairunisak Abdul Razak
- School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, Nibong Tebal, Penang, Malaysia
| | - Moshi Geso
- School of Health and Biomedical Sciences, RMIT University, Bundoora, VIC, Australia
| | - Merfat Algethami
- Faculty of Science, Taif University, Al Hawiyah, Taif, Saudi Arabia
| | - Wan Nordiana Rahman
- School of Health Sciences, Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia
- Correspondence: Wan Nordiana Rahman, School of Health Sciences, Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia, Tel +6097677811, Email
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7
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Mohd Zainudin NH, Talik Sisin NN, Rashid RA, Jamil A, Khairil Anuar MA, Razak KA, Abdullah R, Rahman WN. Cellular analysis on the radiation induced bystander effects due to bismuth oxide nanoparticles with 6 MV photon beam radiotherapy. Journal of Radiation Research and Applied Sciences 2022. [DOI: 10.1016/j.jrras.2022.08.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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8
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Mohamad Nor N, Arivalakan S, Zakaria ND, Nilamani N, Lockman Z, Abdul Razak K. Self-Assembled Iron Oxide Nanoparticle-Modified APTES-ITO Electrode for Simultaneous Stripping Analysis of Cd(II) and Pb(II) Ions. ACS Omega 2022; 7:3823-3833. [PMID: 35128290 PMCID: PMC8812099 DOI: 10.1021/acsomega.1c07158] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Accepted: 01/11/2022] [Indexed: 12/14/2022]
Abstract
![]()
Carboxyl (−COOH)-stabilized
iron oxide nanoparticles (IONPs)
synthesized through co-precipitation were used to modify an indium
tin oxide (ITO) electrode, which was chemically functionalized with
3-aminopropyltriethoxysilane (APTES) for heavy metal detection. The
effect of soaking time (30, 60, 90, and 120 min) of IONP-COOH self-assembled
on an APTES-ITO electrode was studied. Cyclic voltammetry and scanning
electron microscopy were applied to analyze the electrochemical properties
and morphologies of IONP-COOH/APTES-ITO modified electrode. The modified
electrodes were then employed for the simultaneous detection of Cd(II)
and Pb(II) by using square wave anodic stripping voltammetry. At 90
min of soaking time, excellent electrochemical performance and larger
effective surface area (Ae) were obtained.
The linear range for the simultaneous detection of Cd(II) and Pb(II)
ions using the modified electrode was 10–100 ppb with limits
of detection of 0.90 and 0.60 ppb, respectively. The interference
study revealed a low interference effect from Cr(III), Hg(II), Zn(II),
Cu(II), Mg(II), Na(I), and K(I) toward the simultaneous detection
of Cd(II) and Pb(II). Finally, the IONP-COOH/APTES-ITO-modified electrode
was applied to analyze seawater samples and was able to simultaneously
detect Cd(II) and Pb(II) ions.
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Affiliation(s)
- Noorhashimah Mohamad Nor
- School of Materials & Mineral Resources Engineering, Universiti Sains Malaysia, 14300 Nibong Tebal, Pulau Pinang, Malaysia
| | - Sarasijah Arivalakan
- School of Materials & Mineral Resources Engineering, Universiti Sains Malaysia, 14300 Nibong Tebal, Pulau Pinang, Malaysia
| | - Nor Dyana Zakaria
- NanoBiotechnology Research and Innovation (NanoBRI), Institute for Research in Molecular Medicine, Universiti Sains Malaysia, 11800 Penang, Malaysia
| | - Nithiyaa Nilamani
- Centre for Marine and Coastal Studies, Universiti Sains Malaysia, 11800 Penang, Malaysia
| | - Zainovia Lockman
- School of Materials & Mineral Resources Engineering, Universiti Sains Malaysia, 14300 Nibong Tebal, Pulau Pinang, Malaysia
| | - Khairunisak Abdul Razak
- School of Materials & Mineral Resources Engineering, Universiti Sains Malaysia, 14300 Nibong Tebal, Pulau Pinang, Malaysia
- NanoBiotechnology Research and Innovation (NanoBRI), Institute for Research in Molecular Medicine, Universiti Sains Malaysia, 11800 Penang, Malaysia
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9
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Jamil A, Abidin SZ, Razak KA, Zin H, Yunus MA, Rahman WN. Radiosensitization effects by bismuth oxide nanorods of different sizes in megavoltage external beam radiotherapy. Rep Pract Oncol Radiother 2021; 26:773-784. [PMID: 34760312 DOI: 10.5603/rpor.a2021.0094] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 07/03/2021] [Indexed: 11/25/2022] Open
Abstract
Background Nanotechnology application has successfully reached numerous scientific breakthroughs including in radiotherapy. However, the clinical application of nanoparticles requires more diligent research primarily on the crucial parameters such as nanoparticle sizes. This study is aimed to investigate the influence of bismuth oxide nanorod (Bi2O3-NR) sizes on radiosensitization effects on MCF-7 and HeLa cell lines for megavoltage photon and electron beam radiotherapy. Materials and methods MCF-7 and HeLa cells were treated with and without 0.5 μMol/L of Bi2O3-NR of varying sizes (60, 70, 80, and 90 nm). The samples, including the control groups, were exposed to different radiation doses (0-10 Gy), using photon (6 MV and 10 MV), and electron beam (6 MeV and 12 MeV) radiotherapy. Clonogenic assay was performed, and sensitization enhancement ratio (SER) was determined from linear quadratic based cell survival curves. Results The results depicted that 60 nm Bi2O3-NR yields the most excellent SER followed by 70 nm Bi2O3-NR. Meanwhile, the 80 and 90 nm Bi2O3-NR showed an insignificant difference between treated and untreated cell groups. This study also found that MCF-7 was subjected to more cell death compared to HeLa. Conclusion 60 nm Bi2O3-NR was the optimal Bi2O3-NR size to induce radiosensitization effects for megavoltage external beam radiotherapy. The SER in photon beam radiotherapy marked the highest compared to electron beam radiotherapy due to decreased primary radiation energy from multiple radiation interaction and higher Compton scattering.
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Affiliation(s)
- Amirah Jamil
- School of Health Sciences, Health Campus, Universiti Sains Malaysia, Kubang Kerian, Kota Bharu, Kelantan, Malaysia
| | - Safri Zainal Abidin
- School of Health Sciences, Health Campus, Universiti Sains Malaysia, Kubang Kerian, Kota Bharu, Kelantan, Malaysia.,Advanced Medical and Dental Institute, Universiti Sains Malaysia, Bertam, Kepala Batas, Penang Malaysia
| | - Khairunisak Abdul Razak
- School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, Nibong Tebal, Penang, Malaysia
| | - Hafiz Zin
- Advanced Medical and Dental Institute, Universiti Sains Malaysia, Bertam, Kepala Batas, Penang Malaysia
| | - Muhammad Amir Yunus
- Advanced Medical and Dental Institute, Universiti Sains Malaysia, Bertam, Kepala Batas, Penang Malaysia
| | - Wan Nordiana Rahman
- School of Health Sciences, Health Campus, Universiti Sains Malaysia, Kubang Kerian, Kota Bharu, Kelantan, Malaysia
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10
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Budiman F, Tan WK, Kawamura G, Muto H, Matsuda A, Abdul Razak K, Lockman Z. Formation of Dense and High-Aspect-Ratio Iron Oxide Nanowires by Water Vapor-Assisted Thermal Oxidation and Their Cr(VI) Adsorption Properties. ACS Omega 2021; 6:28203-28214. [PMID: 34723018 PMCID: PMC8552462 DOI: 10.1021/acsomega.1c04280] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Accepted: 10/05/2021] [Indexed: 06/13/2023]
Abstract
Coral-like and nanowire (NW) iron oxide nanostructures were produced at 700 and 800 °C, respectively, through thermal oxidation of iron foils in air- and water vapor-assisted conditions. Water vapor-assisted thermal oxidation at 800 °C for 2 h resulted in the formation of highly crystalline α-Fe2O3 NWs with good foil surface coverage, and we propose that their formation was due to a stress-driven surface diffusion mechanism. The Cr(VI) adsorption property of an aqueous solution on α-Fe2O3 NWs was also evaluated after a contact time of 90 min. The NWs had a removal efficiency of 97% in a 225 mg/L Cr(VI) solution (pH 2, 25 °C). The kinetic characteristic of the adsorption was fitted to a pseudo-second-order kinetic model, and isothermal studies indicated that the α-Fe2O3 NWs exhibited an adsorption capacity of 66.26 mg/g. We also investigated and postulated a mechanism of the Cr(VI) adsorption in an aqueous solution of α-Fe2O3 NWs.
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Affiliation(s)
- Faisal Budiman
- Green
Electronic Nanomaterials Group, School of Materials and Mineral Resources
Engineering, Engineering Campus, Universiti
Sains Malaysia, Nibong
Tebal 14300, Penang, Malaysia
- Department
of Electrical Engineering, School of Electrical Engineering, Telkom University, Jl. Telekomunikasi No. 1, Bandung 40257, Indonesia
| | - Wai Kian Tan
- Institute
of Liberal Arts & Sciences, Toyohashi
University of Technology, Toyohashi, Aichi 441-8580, Japan
| | - Go Kawamura
- Department
of Electrical and Electronic Information Engineering, Toyohashi University of Technology, Toyohashi, Aichi 441-8580, Japan
| | - Hiroyuki Muto
- Institute
of Liberal Arts & Sciences, Toyohashi
University of Technology, Toyohashi, Aichi 441-8580, Japan
- Department
of Electrical and Electronic Information Engineering, Toyohashi University of Technology, Toyohashi, Aichi 441-8580, Japan
| | - Atsunori Matsuda
- Department
of Electrical and Electronic Information Engineering, Toyohashi University of Technology, Toyohashi, Aichi 441-8580, Japan
| | - Khairunisak Abdul Razak
- Green
Electronic Nanomaterials Group, School of Materials and Mineral Resources
Engineering, Engineering Campus, Universiti
Sains Malaysia, Nibong
Tebal 14300, Penang, Malaysia
| | - Zainovia Lockman
- Green
Electronic Nanomaterials Group, School of Materials and Mineral Resources
Engineering, Engineering Campus, Universiti
Sains Malaysia, Nibong
Tebal 14300, Penang, Malaysia
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11
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Mohamad Nor N, Ramli NH, Poobalan H, Qi Tan K, Abdul Razak K. Recent Advancement in Disposable Electrode Modified with Nanomaterials for Electrochemical Heavy Metal Sensors. Crit Rev Anal Chem 2021; 53:253-288. [PMID: 34565248 DOI: 10.1080/10408347.2021.1950521] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Heavy metal pollution has gained global attention due to its high toxicity and non-biodegradability, even at a low level of exposure. Therefore, the development of a disposable electrode that is sensitive, simple, portable, rapid, and cost-effective as the sensor platform in electrochemical heavy metal detection is vital. Disposable electrodes have been modified with nanomaterials so that excellent electrochemical properties can be obtained. This review highlights the recent progress in the development of numerous types of disposable electrodes modified with nanomaterials for electrochemical heavy metal detection. The disposable electrodes made from carbon-based, glass-based, and paper-based electrodes are reviewed. In particular, the analytical performance, fabrication technique, and integration design of disposable electrodes modified with metal (such as gold, tin and bismuth), carbon (such as carbon nanotube and graphene), and metal oxide (such as iron oxide and zinc oxide) nanomaterials are summarized. In addition, the role of the nanomaterials in improving the electrochemical performance of the modified disposable electrodes is discussed. Finally, the current challenges and future prospect of the disposable electrode modified with nanomaterials are summarized.
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Affiliation(s)
- Noorhashimah Mohamad Nor
- School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, 14300 Nibong Tebal, Pulau Pinang, Malaysia
| | - Nurul Hidayah Ramli
- School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, 14300 Nibong Tebal, Pulau Pinang, Malaysia
| | - Hemalatha Poobalan
- School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, 14300 Nibong Tebal, Pulau Pinang, Malaysia
| | - Kai Qi Tan
- School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, 14300 Nibong Tebal, Pulau Pinang, Malaysia
| | - Khairunisak Abdul Razak
- School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, 14300 Nibong Tebal, Pulau Pinang, Malaysia.,NanoBiotechnology Research & Innovation (NanoBRI), Institute for Research in Molecular Medicine, Universiti Sains Malaysia, 11800 USM, Pulau Pinang, Malaysia
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12
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Zakaria ND, Omar MH, Ahmad Kamal NN, Abdul Razak K, Sönmez T, Balakrishnan V, Hamzah HH. Effect of Supporting Background Electrolytes on the Nanostructure Morphologies and Electrochemical Behaviors of Electrodeposited Gold Nanoparticles on Glassy Carbon Electrode Surfaces. ACS Omega 2021; 6:24419-24431. [PMID: 34604624 PMCID: PMC8482400 DOI: 10.1021/acsomega.1c02670] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 08/10/2021] [Indexed: 05/25/2023]
Abstract
Electrodeposition is an electrochemical method employed to deposit stable and robust gold nanoparticles (AuNPs) on electrode surfaces for creating chemically modified electrodes (CMEs). The use of several electrodeposition techniques with different experimental parameters allow in obtaining various surface morphologies of AuNPs deposited on the electrode surface. By considering the electrodeposition of AuNPs in various background electrolytes could play an important strategy in finding the most suitable formation of the electrodeposited AuNP films on the electrode surface. This is because different electrode roughnesses can have different effects on the electrochemical activities of the modified electrodes. Thus, in this study, the electrodeposition of AuNPs onto the glassy carbon (GC) electrode surfaces in various aqueous neutral and acidic electrolytes was achieved by using the cyclic voltammetry (CV) technique with no adjustable CV parameters. Then, surface morphologies and electrochemical activities of the electrodeposited AuNPs were investigated using scanning electron microscopy (SEM), atomic force microscopy (AFM), CV, and electrochemical impedance spectroscopy (EIS). The obtained SEM and 3D-AFM images show that AuNPs deposited at the GC electrode prepared in NaNO3 solution form a significantly better, uniform, and homogeneous electrodeposited AuNP film on the GC electrode surface with nanoparticle sizes ranging from ∼36 to 60 nm. Meanwhile, from the electrochemical performances of the AuNP-modified GC electrodes, characterized by using a mixture of ferricyanide and ferrocyanide ions [Fe(CN6)3-/4-], there is no significant difference observed in the case of charge-transfer resistances (R ct) and heterogeneous electron-transfer rate constants (k o), although there are differences in the surface morphologies of the electrodeposited AuNP films. Remarkably, the R ct values of the AuNP-modified GC electrodes are lower than those of the bare GC electrode by 18-fold, as the R ct values were found to be ∼6 Ω (p < 0.001, n = 3). This has resulted in obtaining k o values of AuNP-modified GC electrodes between the magnitude of 10-2 and 10-3 cm s-1, giving a faster electron-transfer rate than that of the bare GC electrode (10-4 cm s-1). This study confirms that using an appropriate supporting background electrolyte plays a critical role in preparing electrodeposited AuNP films. This approach could lead to nanostructures with a more densely, uniformly, and homogeneously electrodeposited AuNP film on the electrode surfaces, albeit utilizing an easy and simple preparation method.
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Affiliation(s)
- Nor Dyana Zakaria
- Institute
for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia (USM), 11800 Gelugor, Penang, Malaysia
| | - Muhamad Huzaifah Omar
- School
of Chemical Sciences, Universiti Sains Malaysia
(USM), 11800 Gelugor, Penang, Malaysia
| | | | - Khairunisak Abdul Razak
- Institute
for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia (USM), 11800 Gelugor, Penang, Malaysia
- School
of Materials and Mineral Resources Engineering, Universiti Sains Malaysia (USM), 14300 Nibong Tebal, Penang, Malaysia
| | - Turgut Sönmez
- Department
of Energy System Engineering, Technology Faculty, Karabük University, 78050 Karabük, Turkey
- Institut
für Technische und Makromolekulare Chemie, RWTH Aachen University, Worringerweg 2, 52074 Aachen, Germany
| | - Venugopal Balakrishnan
- Institute
for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia (USM), 11800 Gelugor, Penang, Malaysia
| | - Hairul Hisham Hamzah
- School
of Chemical Sciences, Universiti Sains Malaysia
(USM), 11800 Gelugor, Penang, Malaysia
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Omar MH, Razak KA, Ab Wahab MN, Hamzah HH. Recent progress of conductive 3D-printed electrodes based upon polymers/carbon nanomaterials using a fused deposition modelling (FDM) method as emerging electrochemical sensing devices. RSC Adv 2021; 11:16557-16571. [PMID: 35479129 PMCID: PMC9031910 DOI: 10.1039/d1ra01987b] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 04/27/2021] [Indexed: 01/05/2023] Open
Abstract
3D-printing or additive manufacturing is presently an emerging technology in the fourth industrial revolution that promises to reshape traditional manufacturing processes. The electrochemistry field can undoubtedly take advantage of this technology to fabricate electrodes to create a new generation of electrode sensor devices that could replace conventionally manufactured electrodes; glassy carbon, screen-printed carbon and carbon composite electrodes. In the electrochemistry research area, studies to date show that there is a demand for electrically 3D printable conductive polymer/carbon nanomaterial filaments where these materials can be printed out through an extrusion process based upon the fused deposition modelling (FDM) method. FDM could be used to manufacture novel electrochemical 3D printed electrode sensing devices for electrochemical sensor and biosensor applications. This is due to the FDM method being the most affordable 3D printing technique since conductive and non-conductive thermoplastic filaments are commercially available. Therefore, in this minireview, we focus on only the most outstanding studies that have been published since 2018. We believe this to be a highly-valuable research area to the scientific community, both in academia and industry, to enable novel ideas, materials, designs and methods relating to electroanalytical sensing devices to be generated. This approach has the potential to create a new generation of electrochemical sensing devices based upon additive manufacturing. This minireview also provides insight into how the research community could improve the electrochemical performance of 3D-printed electrodes to significantly increase the sensitivity of the 3D-printed electrodes as electrode sensing devices.
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Affiliation(s)
- Muhamad Huzaifah Omar
- School of Chemical Sciences, Universiti Sains Malaysia (USM) 11800 Gelugor Penang Malaysia
| | - Khairunisak Abdul Razak
- Nanobiotechnology Research and Innovation (NanoBRI), Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia 11800 Gelugor Penang Malaysia
- School of Materials and Mineral Resources Engineering, Engineering Campus, Universiti Sains Malaysia 14300 Nibong Tebal Penang Malaysia
| | - Mohd Nadhir Ab Wahab
- School of Computer Sciences, Universiti Sains Malaysia 11800 Gelugor Penang Malaysia
| | - Hairul Hisham Hamzah
- School of Chemical Sciences, Universiti Sains Malaysia (USM) 11800 Gelugor Penang Malaysia
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Taib MAA, Alias N, Jaafar M, Razak KA, Tan WK, Shahbudin IP, Kawamura G, Matsuda A, Lockman Z. Formation of grassy TiO 2 nanotube thin film by anodisation in peroxide electrolyte for Cr(VI) removal under ultraviolet radiation. Nanotechnology 2020; 31:435605. [PMID: 32640434 DOI: 10.1088/1361-6528/aba3d8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Arrays of TiO2 nanotubes (TiO2 NTs) with grassy surfaces were observed on titanium foil anodised at 60 V in fluorinated ethylene glycol (EG) with added hydrogen peroxide (H2O2). The grassy surface was generated by the chemical etching and dissolution of the surface of the TiO2 NTs walls, which was accelerated by the temperature increase on the addition of H2O2 . Upon annealing at 600 °C, the grassy part of the TiO2 NTs was found to consist of mostly anatase TiO2 whereas the bottom part of the anodic oxide comprised a mixture of anatase and rutile TiO2. The TiO2 NTs were then used to reduce hexavalent chromium (Cr(VI)) under ultraviolet radiation. They exhibited a rather efficient photocatalytic effect, with 100% removal of Cr(VI) after 30 min of irradiation. The fast removal of Cr(VI) was due to the anatase dominance at the grassy part of the TiO2 NTs as well as the higher surface area the structure may have. This work provides a novel insight into the photocatalytic reduction of Cr(VI) on grassy anatase TiO2 NTs.
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Affiliation(s)
- Mustaffa Ali Azhar Taib
- Green Electronics Oxide nanoMaterials Group (GEM), School of Materials and Mineral Resources Engineering, Engineering Campus, Universiti Sains Malaysia, 14300, Nibong Tebal, Penang, Malaysia. Advanced Technology Training Centre (ADTEC) Taiping, PT 15643, Kamunting Raya, Mukim Asam Kumbang, 34600, Kamunting, Perak, Malaysia
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Rumschlag JA, Lovelace JW, Razak KA. Age- and movement-related modulation of cortical oscillations in a mouse model of presbycusis. Hear Res 2020; 402:108095. [PMID: 33707000 DOI: 10.1016/j.heares.2020.108095] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 08/27/2020] [Accepted: 10/09/2020] [Indexed: 01/29/2023]
Abstract
Brain oscillations are associated with specific cognitive and sensory processes. How age-related hearing loss (presbycusis) alters cortical oscillations is unclear. Altered inhibitory neurotransmission and temporal processing deficits contribute to speech recognition impairments in presbycusis. Specifically, age-related reduction in parvalbumin positive interneurons and perineuronal nets in the auditory cortex predicts a reduction in gamma oscillations that may lead to a decline in temporal precision and attention. To test the hypothesis that resting and evoked gamma oscillations decline with presbycusis, EEGs were recorded from the auditory and frontal cortex of awake, freely moving C57BL/6 J mice at three ages (3, 14 and 24 months). Resting EEG data were analyzed according to movement state (move versus still). Evoked responses were recorded following presentation of noise bursts or amplitude modulated noise with time varying modulation frequencies. We report an age-related decrease in resting gamma power, a decline in gamma-range synchrony to time varying stimuli, and an increase in noise evoked and induced gamma power. A decline in temporal processing is seen in aged mice that exhibit robust auditory-evoked potentials, dissociating hearing loss from temporal processing deficits. We also report an increase in gamma power when mice moved compared to the still state. However, the movement-related modulation of gamma oscillations did not change with age. Together, these data identify a number of novel markers of presbycusis-related changes in auditory and frontal cortex. Because EEGs are commonly recorded in humans, the mouse data may serve as translation relevant preclinical biomarkers to facilitate the development of therapeutics to delay or reverse central auditory processing deficits in presbycusis.
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Affiliation(s)
- J A Rumschlag
- Graduate Neuroscience Program, University of California, Riverside, United States
| | - J W Lovelace
- Psychology Department, University of California, Riverside, United States
| | - K A Razak
- Graduate Neuroscience Program, University of California, Riverside, United States; Psychology Department, University of California, Riverside, United States.
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Talik Sisin NN, Abdul Razak K, Zainal Abidin S, Che Mat NF, Abdullah R, Ab Rashid R, Khairil Anuar MA, Rahman WN. Synergetic Influence of Bismuth Oxide Nanoparticles, Cisplatin and Baicalein-Rich Fraction on Reactive Oxygen Species Generation and Radiosensitization Effects for Clinical Radiotherapy Beams. Int J Nanomedicine 2020; 15:7805-7823. [PMID: 33116502 PMCID: PMC7567565 DOI: 10.2147/ijn.s269214] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 09/22/2020] [Indexed: 12/11/2022] Open
Abstract
Purpose This study aimed to quantify synergetic effects induced by bismuth oxide nanoparticles (BiONPs), cisplatin (Cis) and baicalein-rich fraction (BRF) natural-based agent on the reactive oxygen species (ROS) generation and radiosensitization effects under irradiation of clinical radiotherapy beams of photon, electron and HDR-brachytherapy. The combined therapeutic responses of each compound and clinical radiotherapy beam were evaluated on breast cancer and normal fibroblast cell line. Methods In this study, individual BiONPs, Cis, and BRF, as well as combinations of BiONPs-Cis (BC), BiONPs-BRF (BB) and BiONPs-Cis-BRF (BCB) were treated to the cells before irradiation using HDR brachytherapy with 0.38 MeV iridium-192 source, 6 MV photon beam and 6 MeV electron beam. The individual or synergetic effects from the application of the treatment components during the radiotherapy were elucidated by quantifying the ROS generation and radiosensitization effects on MCF-7 and MDA-MB-231 breast cancer cell lines as well as NIH/3T3 normal cell line. Results The ROS generated in the presence of Cis stimulated the most substantial amount of ROS compared to the BiONPs and BRF. Meanwhile, the combination of the components had induced the higher ROS levels for photon beam than the brachytherapy and electron beam. The highest ROS enhancement relative to the control is attributable to the presence of BC combination in MDA-MB-231 cells, in comparison to the BB and BCB combinations. The radiosensitization effects which were quantified using the sensitization enhancement ratio (SER) indicate the highest value by BC in MCF-7 cells, followed by BCB and BB treatment. The radiosensitization effects are found to be more prominent for brachytherapy in comparison to photon and electron beam. Conclusion The BiONPs, Cis and BRF are the potential radiosensitizers that could improve the efficiency of radiotherapy to eradicate the cancer cells. The combination of these potent radiosensitizers might produce multiple effects when applied in radiotherapy. The BC combination is found to have the highest SER, followed by the BCB combination. This study is also the first to investigate the effect of BRF in combination with BiONPs (BB) and BC (BCB) treatments.
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Affiliation(s)
- Noor Nabilah Talik Sisin
- Medical Radiation Programme, School of Health Sciences, Universiti Sains Malaysia, Kubang Kerian, Kelantan,Malaysia
| | - Khairunisak Abdul Razak
- Material Engineering Programme, School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, Nibong Tebal, Penang, Malaysia
| | - Safri Zainal Abidin
- Oncological and Radiological Sciences Cluster, Advanced Medical and Dental Institute, Universiti Sains Malaysia, Bertam, Penang, Malaysia
| | - Nor Fazila Che Mat
- Medical Radiation Programme, School of Health Sciences, Universiti Sains Malaysia, Kubang Kerian, Kelantan,Malaysia
| | - Reduan Abdullah
- Medical Radiation Programme, School of Health Sciences, Universiti Sains Malaysia, Kubang Kerian, Kelantan,Malaysia.,Nuclear Medicine, Radiotherapy and Oncology Department, Hospital of Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia
| | - Raizulnasuha Ab Rashid
- Medical Radiation Programme, School of Health Sciences, Universiti Sains Malaysia, Kubang Kerian, Kelantan,Malaysia
| | - Muhammad Afiq Khairil Anuar
- Medical Radiation Programme, School of Health Sciences, Universiti Sains Malaysia, Kubang Kerian, Kelantan,Malaysia
| | - Wan Nordiana Rahman
- Medical Radiation Programme, School of Health Sciences, Universiti Sains Malaysia, Kubang Kerian, Kelantan,Malaysia
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Yahaya ML, Zakaria ND, Noordin R, Abdul Razak K. Development of rapid gold nanoparticles based lateral flow assays for simultaneous detection of Shigella and Salmonella genera. Biotechnol Appl Biochem 2020; 68:1095-1106. [PMID: 32935878 DOI: 10.1002/bab.2029] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 09/07/2020] [Indexed: 12/27/2022]
Abstract
Salmonella and Shigella genera are common pathogens that contaminate foods and beverages. Lateral flow assays (LFA) are commonly used to detect these pathogens. However, most of the developed LFAs are for single detection. Simultaneous detection of pathogens is required to reduce cost and time. In this work, 40 nm gold nanoparticles (AuNPs) were synthesized using the seeding growth method as labeling agent. The AuNPs were characterized and conjugated with mouse anti-Gram negative endotoxin antibody. The nitrocellulose membrane HF135 was immobilized with anti-mouse IgG antibody as a control line and two separate test lines with either anti-Shigella or anti-Salmonella antibody, respectively. Color intensity of test lines was observed for positive samples. A milk sample was used as proof of concept to mimic actual contamination. The limit of detection of the LFA was 3.0 × 106 CFU/mL for multiplex detection of Shigella flexneri and Salmonella Typhi and for both single detections. The result was comparable with the enzyme-linked immunosorbent assay (ELISA) analysis. The produced LFA could differentiate between Shigella flexneri, Shigella boydii, Salmonella Enteritidis, and Salmonella Typhi. The developed LFA was able to identify Shigella flexneri and Salmonella Typhi with good sensitivity in milk samples, thus, beneficial to ensure the safety of food before entering the market.
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Affiliation(s)
- Mohammad Lukman Yahaya
- School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, Nibong Tebal, Penang, Malaysia
| | - Nor Dyana Zakaria
- Nanobiotechnology Research and Innovation (NanoBri), Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Nibong Tebal, Penang, Malaysia
| | - Rahmah Noordin
- Nanobiotechnology Research and Innovation (NanoBri), Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Nibong Tebal, Penang, Malaysia
| | - Khairunisak Abdul Razak
- School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, Nibong Tebal, Penang, Malaysia.,Nanobiotechnology Research and Innovation (NanoBri), Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Nibong Tebal, Penang, Malaysia
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Zakaria JB, Abd Shukor SR, Abdul Razak K. EFFECT OF SURFACTANT, SOLVENT AND STIRRING RATE ON THE SYNTHESIS OF SILICA NANOPARTICLES ENTRAPPED RIFAMPICIN. JCEIB 2020; 5:36-47. [DOI: 10.15282/jceib.v5i2.3677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
Abstract
In this study, silica nanoparticles entrapped with rifampicin has successfully been synthesized by using micelles entrapment approach. The goal of this study is to investigate the effects of synthesis parameters; surfactant (Tween 80), solvent (water) and stirring rate on the particles size and distribution of silica nanoparticles entrapped rifampicin. The results showed that without surfactant, larger mean particles (176.4 nm to 207.70 nm) of silica nanoparticles were produced while uniform and smaller spherical particles sizes (42.37 nm -70.44 nm) were formed with the addition of surfactant. But, when the amount of surfactant increased from 3.0 g to 9.0 g, larger silica nanoparticles with uniform size and thinner walls were observed until critical micelle concentration (CMC) of surfactant equivalent to 11.0 g was reached. The effect of water content shows the particle size slightly increased from 55.92 nm to 56.99 nm when the water content was increased from 150 mL to 200 mL, and decreased rapidly from 56.99 nm to 18.55 nm as the amount of water was increased from 200 mL to 350 mL. Meanwhile, for the effect of stirring rate, the mean particles sizes were recorded in the range of 39.11 to 80.15 nm. The largest size was observed at the lowest stirring rate (120 rpm) and the smallest size was observed at the highest stirring rate (520 rpm). The significant effect of these synthesis parameters can be used in developing a rational basis in tuning the size of silica nanoparticles for drug delivery system.
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Alias N, Rosli SA, Sazalli NAH, Hamid HA, Arivalakan S, Umar SNH, Khim BK, Taib BN, Keat YK, Razak KA, Yee YF, Hussain Z, Bakar EA, Kamaruddin NF, Manaf AA, Uchiyama N, Kian TW, Matsuda A, Kawamura G, Sawada K, Matsumoto A, Lockman Z. Metal oxide for heavy metal detection and removal. Metal Oxide Powder Technologies 2020:299-332. [DOI: 10.1016/b978-0-12-817505-7.00015-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
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20
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Sisin NNT, Abdul Razak K, Zainal Abidin S, Che Mat NF, Abdullah R, Ab Rashid R, Khairil Anuar MA, Mohd Zainudin NH, Tagiling N, Mat Nawi N, Rahman WN. Radiosensitization Effects by Bismuth Oxide Nanoparticles in Combination with Cisplatin for High Dose Rate Brachytherapy. Int J Nanomedicine 2019; 14:9941-9954. [PMID: 31908451 PMCID: PMC6927229 DOI: 10.2147/ijn.s228919] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 10/22/2019] [Indexed: 12/18/2022] Open
Abstract
Purpose The aim of this study was to investigate the potential of the synergetic triple therapeutic combination encompassing bismuth oxide nanoparticles (BiONPs), cisplatin (Cis), and high dose rate (HDR) brachytherapy with Ir-192 source in breast cancer and normal fibroblast cell line. Methods In vitro models of breast cancer cell lines (MCF-7, MDA-MB-231) and normal fibroblast cell line (NIH/3T3) were employed. Cellular localization and cytotoxicity studies were conducted prior to inspection on the radiosensitization effects and generation of reactive oxygen species (ROS) on three proposed radiosensitizers: BiONPs, Cis, and BiONPs-Cis combination (BC). The optimal, non-cytotoxic concentration of BiONPs (0.5 mM) and the 25% inhibitory concentration of Cis (1.30 µM) were applied. The radiosensitization effects were evaluated by using a 0.38 MeV Iridium-192 HDR brachytherapy source over a prescribed dose range of 0 Gy to 4 Gy. Results The cellular localization of BiONPs was visualized by light microscopy and accumulation of the BiONPs within the vicinity of the nuclear membrane was observed. Quantification of the sensitization enhancement ratio extrapolated from the survival curves indicates radiosensitization effects for MCF-7 and MDA-MB-231 when treated with BiONPs, Cis, and BC. However, NIH/3T3 cells exhibited contradictive behavior as it only reacted towards the BC combination. Nonetheless, the MCF-7 cell line loaded with BC shows the highest SER of 4.29. ROS production analysis, on the other hand, shows that Cis and BC radiosensitizers generated the highest free radicals in comparison to BiONPs alone. Conclusion A BiONPs-Cis combination was unveiled as a novel approach that offers promising radiosensitization enhancement that will increase the efficiency of tumor control while preserving the normal tissue at a reduced dose. This data is the first precedent to prove the synergetic implication of BiONPs, Cis, and HDR brachytherapy that will be beneficial for future chemoradiotherapy strategies in cancer care.
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Affiliation(s)
| | - Khairunisak Abdul Razak
- School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, Nibong Tebal, Penang, Malaysia
| | - Safri Zainal Abidin
- Advanced Medical and Dental Institute, Universiti Sains Malaysia, Bertam, Penang, Malaysia
| | - Nor Fazila Che Mat
- School of Health Sciences, Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia
| | - Reduan Abdullah
- School of Health Sciences, Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia.,Hospital of Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia
| | | | | | | | - Nashrulhaq Tagiling
- School of Health Sciences, Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia
| | - Norazlina Mat Nawi
- School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia
| | - Wan Nordiana Rahman
- School of Health Sciences, Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia
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Abidin SZ, Zulkifli ZA, Razak KA, Zin H, Yunus MA, Rahman WN. PEG coated bismuth oxide nanorods induced radiosensitization on MCF-7 breast cancer cells under irradiation of megavoltage radiotherapy beams. ACTA ACUST UNITED AC 2019. [DOI: 10.1016/j.matpr.2019.06.029] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abdul Rashid R, Zainal Abidin S, Khairil Anuar MA, Tominaga T, Akasaka H, Sasaki R, Kie K, Abdul Razak K, Pham BT, Hawkett BS, Carmichael MA, Geso M, Rahman WN. Radiosensitization effects and ROS generation by high Z metallic nanoparticles on human colon carcinoma cell (HCT116) irradiated under 150 MeV proton beam. OpenNano 2019. [DOI: 10.1016/j.onano.2018.100027] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Bashirom N, Kian TW, Kawamura G, Matsuda A, Razak KA, Lockman Z. Sunlight activated anodic freestanding ZrO 2 nanotube arrays for Cr(VI) photoreduction. Nanotechnology 2018; 29:375701. [PMID: 29901455 DOI: 10.1088/1361-6528/aaccbd] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Visible-light-active freestanding zirconia (ZrO2) nanotube (FSZNT) arrays were fabricated by a facile electrochemical anodization method in fluoride containing ethylene glycol electrolyte added to it was 1 vol% of potassium carbonate (K2CO3) at 60 V for 1 h. Poor adhesion at the metal∣oxide interface was induced by K2CO3 leading to the formation of FSZNT flakes. The effect of the crystal structures of the FSZNTs e.g., amorphous, amorphous/tetragonal, and tetragonal/monoclinic was investigated towards the photocatalytic reduction of 10 ppm hexavalent chromium, Cr(VI) at pH 2 under sunlight. The results demonstrate the amorphous FSZNTs exhibited the highest Cr(VI) removal efficiency than the crystalline FSZNTs (95% versus 33% after 5 h). The high photocatalytic activity of the amorphous FSZNTs can be attributed to enhanced Cr(VI) adsorption, high visible light absorption, and better charge carrier separation. The low photocatalytic activity of the crystalline FSZNTs annealed at 500 °C was mainly attributed to poor Cr(VI) adsorption, low visible light absorption, and less photoactive monoclinic-ZrO2.
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Affiliation(s)
- Nurulhuda Bashirom
- School of Materials Engineering, Universiti Malaysia Perlis, Kompleks Pusat Pengajian Jejawi 2, Taman Muhibbah, 02600 Jejawi, Arau, Perlis, Malaysia. Green Electronics Nanomaterials Group, School of Materials & Mineral Resources Engineering, Universiti Sains Malaysia, 14300 Seri Ampangan, Nibong Tebal, Seberang Prai Selatan, Pulau Pinang, Malaysia
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Ridhuan NS, Abdul Razak K, Lockman Z. Fabrication and Characterization of Glucose Biosensors by Using Hydrothermally Grown ZnO Nanorods. Sci Rep 2018; 8:13722. [PMID: 30213995 PMCID: PMC6137152 DOI: 10.1038/s41598-018-32127-5] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 08/31/2018] [Indexed: 11/24/2022] Open
Abstract
Highly oriented ZnO nanorod (NR) arrays were fabricated on a seeded substrate through a hydrothermal route. The prepared ZnO nanorods were used as an amperometric enzyme electrode, in which glucose oxidase (GOx) was immobilised through physical adsorption. The modified electrode was designated as Nafion/GOx/ZnO NRs/ITO. The morphology and structural properties of the fabricated ZnO nanorods were analysed using field-emission scanning electron microscope and X-ray diffractometer. The electrochemical properties of the fabricated biosensor were studied by cyclic voltammetry and amperometry. Electrolyte pH, electrolyte temperature and enzyme concentration used for immobilisation were the examined parameters influencing enzyme activity and biosensor performance. The immobilised enzyme electrode showed good GOx retention activity. The amount of electroactive GOx was 7.82 × 10−8 mol/cm2, which was relatively higher than previously reported values. The Nafion/GOx/ZnO NRs/ITO electrode also displayed a linear response to glucose ranging from 0.05 mM to 1 mM, with a sensitivity of 48.75 µA/mM and a low Michaelis–Menten constant of 0.34 mM. Thus, the modified electrode can be used as a highly sensitive third-generation glucose biosensor with high resistance against interfering species, such as ascorbic acid, uric acid and L-cysteine. The applicability of the modified electrode was tested using human blood samples. Results were comparable with those obtained using a standard glucometer, indicating the excellent performance of the modified electrode.
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Affiliation(s)
- Nur Syafinaz Ridhuan
- School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, 14300, Nibong Tebal, Penang, Malaysia
| | - Khairunisak Abdul Razak
- School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, 14300, Nibong Tebal, Penang, Malaysia. .,NanoBiotechnology Research & Innovation (NanoBRI), INFORMM, Universiti Sains Malaysia, 11800 USM, Gelugor, Penang, Malaysia.
| | - Zainovia Lockman
- School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, 14300, Nibong Tebal, Penang, Malaysia
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Sinclair D, Oranje B, Razak KA, Siegel SJ, Schmid S. Sensory processing in autism spectrum disorders and Fragile X syndrome-From the clinic to animal models. Neurosci Biobehav Rev 2017; 76:235-253. [PMID: 27235081 PMCID: PMC5465967 DOI: 10.1016/j.neubiorev.2016.05.029] [Citation(s) in RCA: 114] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 04/08/2016] [Accepted: 05/23/2016] [Indexed: 01/08/2023]
Abstract
Brains are constantly flooded with sensory information that needs to be filtered at the pre-attentional level and integrated into endogenous activity in order to allow for detection of salient information and an appropriate behavioral response. People with Autism Spectrum Disorder (ASD) or Fragile X Syndrome (FXS) are often over- or under-reactive to stimulation, leading to a wide range of behavioral symptoms. This altered sensitivity may be caused by disrupted sensory processing, signal integration and/or gating, and is often being neglected. Here, we review translational experimental approaches that are used to investigate sensory processing in humans with ASD and FXS, and in relevant rodent models. This includes electroencephalographic measurement of event related potentials, neural oscillations and mismatch negativity, as well as habituation and pre-pulse inhibition of startle. We outline robust evidence of disrupted sensory processing in individuals with ASD and FXS, and in respective animal models, focusing on the auditory sensory domain. Animal models provide an excellent opportunity to examine common mechanisms of sensory pathophysiology in order to develop therapeutics.
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Affiliation(s)
- D Sinclair
- Translational Neuroscience Program, Department of Psychiatry, University of Pennsylvania, 125 S 31st St., Philadelphia, PA 19104, USA
| | - B Oranje
- Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht, HP A 01.126 Heidelberglaan 100, CX Utrecht, 3584, The Netherlands; Center for Neuropsychiatric Schizophrenia Research (CNSR) and Center for Clinical Intervention and Neuropsychiatric Schizophrenia Research (CINS), Copenhagen University Hospital, Psychiatric Center Glostrup, Ndr. Ringvej 29-67, Glostrup, 2600, Denmark; Faculty of Health Sciences, Department of Neurology, Psychiatry, and Sensory Sciences, University of Copenhagen, Denmark
| | - K A Razak
- Psychology Department, University of California Riverside, 900 University Avenue, Riverside, CA 92521, USA
| | - S J Siegel
- Translational Neuroscience Program, Department of Psychiatry, University of Pennsylvania, 125 S 31st St., Philadelphia, PA 19104, USA
| | - S Schmid
- Anatomy & Cell Biology, Schulich School of Medicine and Dentistry, University of Western Ontario, MSB 470, London, ON N6A 5C1, Canada.
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Nor NM, Lockman Z, Razak KA. Study of ITO Glass Electrode Modified with Iron Oxide Nanoparticles and Nafion for Glucose Biosensor Application. ACTA ACUST UNITED AC 2016. [DOI: 10.1016/j.proche.2016.03.116] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Budiman F, Kian TW, Razak KA, Matsuda A, Lockman Z. The Assessment of Cr(VI) Removal by Iron Oxide Nanosheets and Nanowires Synthesized by Thermal Oxidation of Iron in Water Vapour. ACTA ACUST UNITED AC 2016. [DOI: 10.1016/j.proche.2016.03.057] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Makhadmeh GN, Abdul Aziz A, Abdul Razak K, Abu Noqta O. Encapsulation efficacy of natural and synthetic photosensitizers by silica nanoparticles for photodynamic applications. IET Nanobiotechnol 2015; 9:381-5. [DOI: 10.1049/iet-nbt.2015.0003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Affiliation(s)
- Ghaseb Naser Makhadmeh
- School of PhysicsUniversiti Sains Malaysia11800 USMPenangMalaysia
- NanoBiotechnology Research and Innovation (NanoBRI)Institute for Research in Molecular Medicine (INFORMM)Universiti Sains Malaysia11800 USMPenangMalaysia
| | - Azlan Abdul Aziz
- School of PhysicsUniversiti Sains Malaysia11800 USMPenangMalaysia
- NanoBiotechnology Research and Innovation (NanoBRI)Institute for Research in Molecular Medicine (INFORMM)Universiti Sains Malaysia11800 USMPenangMalaysia
| | - Khairunisak Abdul Razak
- NanoBiotechnology Research and Innovation (NanoBRI)Institute for Research in Molecular Medicine (INFORMM)Universiti Sains Malaysia11800 USMPenangMalaysia
- School of Materials and Mineral Resources EngineeringUniversiti Sains Malaysia14300 Nibong TebalPenangMalaysia
| | - Osama Abu Noqta
- School of PhysicsUniversiti Sains Malaysia11800 USMPenangMalaysia
- NanoBiotechnology Research and Innovation (NanoBRI)Institute for Research in Molecular Medicine (INFORMM)Universiti Sains Malaysia11800 USMPenangMalaysia
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Makhadmeh GN, Abdul Aziz A, Abdul Razak K. Artificial tissue sensitized with encapsulated methylene blue encapsulated by silica nanoparticles in photodynamic therapy. Artificial Cells, Nanomedicine, and Biotechnology 2015; 44:1285-9. [DOI: 10.3109/21691401.2015.1024843] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Ghaseb Naser Makhadmeh
- School of Physics, Universiti Sains Malaysia, USM, Penang, Malaysia
- NanoBiotechnology Research and Innovation (NanoBRI), Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, USM, Penang, Malaysia
| | - Azlan Abdul Aziz
- NanoBiotechnology Research and Innovation (NanoBRI), Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, USM, Penang, Malaysia
| | - Khairunisak Abdul Razak
- School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, Nibong Tebal, Penang, Malaysia
- NanoBiotechnology Research and Innovation (NanoBRI), Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, USM, Penang, Malaysia
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Makhadmeh GN, Abdul Aziz A, Abdul Razak K. The efficacy of methylene blue encapsulated in silica nanoparticles compared to naked methylene blue for photodynamic applications. Artif Cells Nanomed Biotechnol 2015; 44:1018-22. [PMID: 25707443 DOI: 10.3109/21691401.2015.1008511] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND/AIMS This study analyzed the physical effects of methylene blue (MB) encapsulated within silica nanoparticles (SiNPs) in photodynamic therapy. MATERIALS AND METHODS The optimum concentration of MB needed to destroy red blood cells (RBCs) was determined, and the efficacy of encapsulated MB-SiNPs compared to that of naked MB was verified. RESULTS The results confirmed the applicability of MB encapsulated in SiNPs on RBCs, and established a relationship between the concentration of the SiNP-encapsulated MB and the time required to rupture 50% of the RBCs (t50). CONCLUSION The MB encapsulated in SiNPs exhibited higher efficacy compared to that of naked MB.
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Affiliation(s)
- Ghaseb Naser Makhadmeh
- a Physics Department, School of Physics , Universiti Sains Malaysia , Penang , Malaysia.,c NanoBiotechnology Research and Innovation (NanoBRI), Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia , Penang , Malaysia
| | - Azlan Abdul Aziz
- a Physics Department, School of Physics , Universiti Sains Malaysia , Penang , Malaysia.,c NanoBiotechnology Research and Innovation (NanoBRI), Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia , Penang , Malaysia
| | - Khairunisak Abdul Razak
- b Engineering Department, School of Materials and Mineral Resources Engineering , Universiti Sains Malaysia , Penang , Malaysia.,c NanoBiotechnology Research and Innovation (NanoBRI), Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia , Penang , Malaysia
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Saidin S, Yunus MH, Zakaria ND, Razak KA, Huat LB, Othman N, Noordin R. Erratum To: Production of recombinant Entamoeba histolyticapyruvate phosphate dikinase and its application in a lateral flow dipstick test for amoebic liver abscess. BMC Infect Dis 2014. [PMCID: PMC4464861 DOI: 10.1186/1471-2334-14-533] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Saidin S, Yunus MH, Zakaria ND, Razak KA, Huat LB, Othman N, Noordin R. Production of recombinant Entamoeba histolytica pyruvate phosphate dikinase and its application in a lateral flow dipstick test for amoebic liver abscess. BMC Infect Dis 2014; 14:182. [PMID: 24708664 PMCID: PMC3986461 DOI: 10.1186/1471-2334-14-182] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Accepted: 03/21/2014] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Amoebic liver abscess (ALA) is the most common clinical manifestation of extraintestinal amoebiasis especially in developing countries, causing up to 100 000 fatal cases annually. Accurate and early diagnosis is important to prevent the disease complications, however its diagnosis still poses many challenges due to the limitations of the available detection tools. Pyruvate phosphate dikinase (PPDK), an excretory-secretory protein of E. histolytica, has been reported as a potential diagnostic marker for ALA, hence it may be exploited in the development of a new test for ALA. METHODS Recombinant PPDK (rPPDK) was expressed, purified and evaluated by Western blot. In parallel, recombinant galactose-and-N-acetyl-D-galactosamine inhibitable lectin (Gal/GalNAc lectin) was produced and tested similarly. The protein identity was confirmed by analysis using MALDI-TOF/TOF. A lateral flow dipstick (LFD) test using rPPDK was subsequently developed (rPPDK-LFD) and evaluated for serodiagnosis of ALA. RESULTS rPPDK was expressed as soluble protein after 4 hours of induction with 1 mM isopropyl β-D-1-thiogalactopyranoside (IPTG) at 30°C. Purification using nickel-nitrilotriacetic acid (Ni-NTA) resin yielded 1.5 mg of rPPDK from 1 L of culture with estimated molecular mass of 98 kDa on SDS-PAGE. Western blots using sera from patients with ALA, healthy individuals and other diseases probed with anti-human IgG4-HRP showed the highest sensitivity (93.3%) and specificity (100%); as compared to blots using IgG and IgG1 as secondary antibodies. Moreover, rPPDK showed better specificity when compared to rGal/GalNAc lectin. In the development of the LFD test, the optimum amount of rPPDK was 0.625 μg per dipstick and the optimum working concentration of colloidal gold conjugated anti-human IgG4 was optical density (OD) 5 (1.7 μg of anti-human IgG4). Evaluation of rPPDK-LFD using ALA patients and controls serum samples showed 87% diagnostic sensitivity and 100% specificity. CONCLUSION The developed rPPDK-LFD showed good potential for rapid diagnosis of ALA, and merit further multicentre validation using larger number of serum samples.
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Affiliation(s)
- Syazwan Saidin
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Penang 11800, Malaysia
| | - Muhammad Hafiznur Yunus
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Penang 11800, Malaysia
| | - Nor Dyana Zakaria
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Penang 11800, Malaysia
| | - Khairunisak Abdul Razak
- School of Materials and Mineral Resources Engineering, Engineering Campus, Universiti Sains Malaysia, 14300 Nibong Tebal, Penang, Malaysia
- NanoBiotechnology Research and Innovation (NanoBRI) Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Penang 11800, Malaysia
| | - Lim Boon Huat
- School of Health Sciences, Universiti Sains Malaysia, Kubang Kerian, Kelantan 16150, Malaysia
| | - Nurulhasanah Othman
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Penang 11800, Malaysia
| | - Rahmah Noordin
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Penang 11800, Malaysia
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Tan WK, Li LC, Razak KA, Kawamura G, Muto H, Matsuda A, Lockman Z. Formation of two-dimensional ZnO nanosheets by rapid thermal oxidation in oxygenated environment. J Nanosci Nanotechnol 2014; 14:2960-2967. [PMID: 24734717 DOI: 10.1166/jnn.2014.8559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Crystalline 2-D (dimensional) ZnO nanosheets were formed by rapid thermal oxidation of etched Zn foil in oxygen at 300 degrees C and 400 degrees C. Short oxidation time was varied from 10, 20 and 30 min. The morphologies and optical properties of the ZnO nanosheets evolved with the oxidation temperature and time. At 300 degrees C, ZnO nanosheets with thickness ranging from 32 nm to 80 nm were obtained while at 400 degrees C, the thickness of the nanosheets increased from 88 nm to approximately 200 nm after 10 and 30 min of oxidation, respectively. The surface roughness of the ZnO nanosheets and grain size increased with oxidation time and temperature. Photoluminescence of the oxidized samples shows ultraviolet (UV) and visible emissions indicating good crystallinity of ZnO which was further confirmed by high-resolution transmission electron microscope observation of ZnO wurtzite interplanar spacing. Photocatalytic activity of ZnO was also investigated by using degradation of methyl orange (MO) and all the samples exhibit photocatalytic activity. The sample oxidized at 400 degrees C for 10 min show better MO degradation after 2 h of exposure due to higher surface area and better crystallinity of the ZnO nanosheets obtained.
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Tan WK, Abdul Razak K, Lockman Z, Kawamura G, Muto H, Matsuda A. Synthesis of ZnO nanorod–nanosheet composite via facile hydrothermal method and their photocatalytic activities under visible-light irradiation. J SOLID STATE CHEM 2014. [DOI: 10.1016/j.jssc.2013.12.026] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Khan A, Othman MBH, Razak KA, Akil HM. Synthesis and physicochemical investigation of chitosan-PMAA-based dual-responsive hydrogels. J Polym Res 2013. [DOI: 10.1007/s10965-013-0273-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Makhsin SR, Razak KA, Noordin R, Zakaria ND, Chun TS. The effects of size and synthesis methods of gold nanoparticle-conjugated MαHIgG4 for use in an immunochromatographic strip test to detect brugian filariasis. Nanotechnology 2012; 23:495719. [PMID: 23164811 DOI: 10.1088/0957-4484/23/49/495719] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This study describes the properties of colloidal gold nanoparticles (AuNPs) with sizes of 20, 30 and 40 nm, which were synthesized using citrate reduction or seeding-growth methods. Likewise, the conjugation of these AuNPs to mouse anti-human IgG(4) (MαHIgG(4)) was evaluated for an immunochromatographic (ICG) strip test to detect brugian filariasis. The morphology of the AuNPs was studied based on the degree of ellipticity (G) of the transmission electron microscopy images. The AuNPs produced using the seeding-growth method showed lower ellipticity (G ≤ 1.11) as compared with the AuNPs synthesized using the citrate reduction method (G ≤ 1.18). Zetasizer analysis showed that the AuNPs that were synthesized using the seeding-growth method were almost monodispersed with a lower polydispersity index (PDI; PDI≤0.079), as compared with the AuNPs synthesized using the citrate reduction method (PDI≤0.177). UV-visible spectroscopic analysis showed a red-shift of the absorbance spectra after the reaction with MαHIgG(4), which indicated that the AuNPs were successfully conjugated. The optimum concentration of the BmR1 recombinant antigen that was immobilized on the surface of the ICG strip on the test line was 1.0 mg ml(-1). When used with the ICG test strip assay and brugian filariasis serum samples, the conjugated AuNPs-MαHIgG(4) synthesized using the seeding-growth method had faster detection times, as compared with the AuNPs synthesized using the citrate reduction method. The 30 nm AuNPs-MαHIgG(4), with an optical density of 4 from the seeding-growth method, demonstrated the best performance for labelling ICG strips because it displayed the best sensitivity and the highest specificity when tested with serum samples from brugian filariasis patients and controls.
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Affiliation(s)
- Siti Rabizah Makhsin
- School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, 14300 Nibong Tebal, Penang, Malaysia
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Ridhuan NS, Abdul Razak K, Lockman Z, Abdul Aziz A. Structural and morphology of ZnO nanorods synthesized using ZnO seeded growth hydrothermal method and its properties as UV sensing. PLoS One 2012. [PMID: 23189199 PMCID: PMC3506593 DOI: 10.1371/journal.pone.0050405] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In this study, zinc oxide (ZnO) nanorod arrays were synthesized using a simple hydrothermal reaction on ZnO seeds/n-silicon substrate. Several parameters were studied, including the heat-treatment temperature to produce ZnO seeds, zinc nitrate concentration, pH of hydrothermal reaction solution, and hydrothermal reaction time. The optimum heat-treatment temperature to produce uniform nanosized ZnO seeds was 400°C. The nanorod dimensions depended on the hydrothermal reaction parameters. The optimum hydrothermal reaction parameters to produce blunt tip-like nanorods (770 nm long and 80 nm in top diameter) were 0.1 M zinc nitrate, pH 7, and 4 h of growth duration. Phase analysis studies showed that all ZnO nanorods exhibited a strong (002) peak. Thus, the ZnO nanorods grew in a c-axis preferred orientation. A strong ultraviolet (UV) emission peak was observed for ZnO nanorods grown under optimized parameters with a low, deep-level emission peak, which indicated high optical property and crystallinity of the nanorods. The produced ZnO nanorods were also tested for their UV-sensing properties. All samples responded to UV light but with different sensing characteristics. Such different responses could be attributed to the high surface-to-volume ratio of the nanorods that correlated with the final ZnO nanorods morphology formed at different synthesis parameters. The sample grown using optimum synthesis parameters showed the highest responsivity of 0.024 A/W for UV light at 375 nm under a 3 V bias.
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Affiliation(s)
- Nur Syafinaz Ridhuan
- School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, Nibong Tebal, Penang, Malaysia
| | - Khairunisak Abdul Razak
- School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, Nibong Tebal, Penang, Malaysia
- NanoBiotechnology Research and Innovation, Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Georgetown, Penang, Malaysia
- * E-mail:
| | - Zainovia Lockman
- School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, Nibong Tebal, Penang, Malaysia
| | - Azlan Abdul Aziz
- NanoBiotechnology Research and Innovation, Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Georgetown, Penang, Malaysia
- School of Physics, Universiti Sains Malaysia, Georgetown, Penang, Malaysia
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Goh LP, Razak KA, Ridhuan NS, Cheong KY, Ooi PC, Aw KC. Direct formation of gold nanoparticles on substrates using a novel ZnO sacrificial templated-growth hydrothermal approach and their properties in organic memory device. Nanoscale Res Lett 2012; 7:563. [PMID: 23046949 PMCID: PMC3526390 DOI: 10.1186/1556-276x-7-563] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2012] [Accepted: 09/09/2012] [Indexed: 06/01/2023]
Abstract
This study describes a novel fabrication technique to grow gold nanoparticles (AuNPs) directly on seeded ZnO sacrificial template/polymethylsilsesquioxanes (PMSSQ)/Si using low-temperature hydrothermal reaction at 80°C for 4 h. The effect of non-annealing and various annealing temperatures, 200°C, 300°C, and 400°C, of the ZnO-seeded template on AuNP size and distribution was systematically studied. Another PMMSQ layer was spin-coated on AuNPs to study the memory properties of organic insulator-embedded AuNPs. Well-distributed and controllable AuNP sizes were successfully grown directly on the substrate, as observed using a field emission scanning electron microscope followed by an elemental analysis study. A phase analysis study confirmed that the ZnO sacrificial template was eliminated during the hydrothermal reaction. The AuNP formation mechanism using this hydrothermal reaction approach was proposed. In this study, the AuNPs were charge-trapped sites and showed excellent memory effects when embedded in PMSSQ. Optimum memory properties of PMMSQ-embedded AuNPs were obtained for AuNPs synthesized on a seeded ZnO template annealed at 300°C, with 54 electrons trapped per AuNP and excellent current-voltage response between an erased and programmed device.
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Affiliation(s)
- Lean Poh Goh
- School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, Nibong Tebal, Penang 14300, Malaysia
| | - Khairunisak Abdul Razak
- School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, Nibong Tebal, Penang 14300, Malaysia
- NanoBiotechnology Research and Innovation, INFORMM, Universiti Sains Malaysia, USM, Penang, 11800, Malaysia
| | - Nur Syafinaz Ridhuan
- School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, Nibong Tebal, Penang 14300, Malaysia
- NanoBiotechnology Research and Innovation, INFORMM, Universiti Sains Malaysia, USM, Penang, 11800, Malaysia
| | - Kuan Yew Cheong
- School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, Nibong Tebal, Penang 14300, Malaysia
| | - Poh Choon Ooi
- Mechanical Engineering, The University of Auckland, Auckland, 1142, New Zealand
| | - Kean Chin Aw
- Mechanical Engineering, The University of Auckland, Auckland, 1142, New Zealand
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Abstract
This study focused on mechanisms underlying azimuth selectivity in the primary auditory cortex (A1) of pallid bats. The pallid bat listens to prey-generated noise (5-35 kHz) to localize and hunt terrestrial prey. The region of A1 tuned between 5 and 35 kHz consists of two clusters of neurons distinguished by interaural intensity difference (IID) selectivity: binaurally inhibited (EI) and peaked. The first aim of this study was to use sequential dichotic/free-field stimulation to test the hypothesis that IID is the primary cue underlying azimuth selectivity in neurons tuned in the prey-generated noise frequency band. IID selectivity and ear directionality at the neuron's characteristic frequency (CF) were used to predict azimuth selectivity functions. The predicted azimuth selectivity was compared with the actual azimuth selectivity from the same neurons. Prediction accuracy was similarly high for EI neurons and peaked neurons with low CF, whereas predictions were increasingly inaccurate with increasing CF among the peaked neurons. The second aim of this study was to compare azimuth selectivity obtained with noise and CF tones to determine the extent to which stimulus bandwidth influences azimuth selectivity in neurons with different binaural properties. The azimuth selectivity functions were similar for the two stimuli in the majority of EI neurons. A greater percentage of peaked neurons showed differences in their azimuth selectivity for noise and tones. This included neurons with multiple peaks when tested with tones and a single peak when tested with noise. Taken together, data from the two aims suggest that azimuth tuning of EI neurons is primarily dictated by IID sensitivity at CF. Peaked neurons, particularly those with high CF, may integrate IID sensitivity across frequency to generate azimuth selectivity for broadband sound. The data are consistent with those found in cat and ferret A1 in that binaurally facilitated neurons depend to a greater extent (compared to EI neurons) on spectral integration of binaural properties to generate azimuth selectivity for broadband stimuli.
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Affiliation(s)
- K A Razak
- Department of Psychology, Graduate Neuroscience Program, 900 University Avenue, University of California, Riverside, CA 92521, USA.
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Abstract
Frequency-modulated (FM) sweeps are common components of species-specific vocalizations. The intensity of FM sweeps can cover a wide range in the natural environment, but whether intensity affects neural selectivity for FM sweeps is unclear. Bats, such as the pallid bat, which use FM sweeps for echolocation, are suited to address this issue, because the intensity of echoes will vary with target distance. In this study, FM sweep rate selectivity of pallid bat auditory cortex neurons was measured using downward sweeps at different intensities. Neurons became more selective for FM sweep rates present in the bat's echolocation calls as intensity increased. Increased selectivity resulted from stronger inhibition of responses to slower sweep rates. The timing and bandwidth of inhibition generated by frequencies on the high side of the excitatory tuning curve [sideband high-frequency inhibition (HFI)] shape rate selectivity in cortical neurons in the pallid bat. To determine whether intensity-dependent changes in FM rate selectivity were due to altered inhibition, the timing and bandwidth of HFI were quantified at multiple intensities using the two-tone inhibition paradigm. HFI arrived faster relative to excitation as sound intensity increased. The bandwidth of HFI also increased with intensity. The changes in HFI predicted intensity-dependent changes in FM rate selectivity. These data suggest that neural selectivity for a sweep parameter is not static but shifts with intensity due to changes in properties of sideband inhibition.
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Affiliation(s)
- K A Razak
- Dept. of Psychology, Graduate Neuroscience Program, Univ. of California, Riverside, CA 92521, USA.
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Di Marco M, Shamsuddin S, Razak KA, Aziz AA, Devaux C, Borghi E, Levy L, Sadun C. Overview of the main methods used to combine proteins with nanosystems: absorption, bioconjugation, and encapsulation. Int J Nanomedicine 2010; 5:37-49. [PMID: 20161986 PMCID: PMC2819905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
Abstract
The latest development of protein engineering allows the production of proteins having desired properties and large potential markets, but the clinical advances of therapeutical proteins are still limited by their fragility. Nanotechnology could provide optimal vectors able to protect from degradation therapeutical biomolecules such as proteins, enzymes or specific polypeptides. On the other hand, some proteins can be also used as active ligands to help nanoparticles loaded with chemotherapeutic or other drugs to reach particular sites in the body. The aim of this review is to provide an overall picture of the general aspects of the most successful approaches used to combine proteins with nanosystems. This combination is mainly achieved by absorption, bioconjugation and encapsulation. Interactions of nanoparticles with biomolecules and caveats related to protein denaturation are also pointed out. A clear understanding of nanoparticle-protein interactions could make possible the design of precise and versatile hybrid nanosystems. This could further allow control of their pharmacokinetics as well as activity, and safety.
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Affiliation(s)
- Mariagrazia Di Marco
- Nanobiotix, Paris, France,Correspondence: Maria Di Marco Nanobiotix, 60 rue de Wattignies, 75012 Paris, France, Tel +33 1 40 26 06 26, Fax +33 1 40 26 04 44, Email
| | - Shaharum Shamsuddin
- School of Health Sciences, Health Campus Universiti Sains Malaysia, Kelantan, Malaysia
| | | | | | | | | | | | - Claudia Sadun
- Department of Chemistry, Sapienza, University of Rome, Rome, Italy
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Carrasco MM, Razak KA, Pallas SL. Visual Experience Is Necessary for Maintenance But Not Development of Receptive Fields in Superior Colliculus. J Neurophysiol 2005; 94:1962-70. [PMID: 15917326 DOI: 10.1152/jn.00166.2005] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Sensory deprivation is thought to have an adverse effect on visual development and to prolong the critical period for plasticity. Once the animal reaches adulthood, however, synaptic connectivity is understood to be largely stable. We reported previously that N-methyl-d-aspartate (NMDA) receptor blockade in the superior colliculus of the Syrian hamster prevents refinement of receptive fields (RFs) in normal or compressed retinotopic projections, resulting in target neurons with enlarged RFs but normal stimulus tuning. Here we asked whether visually driven activity is necessary for refinement or maintenance of retinotopic maps or if spontaneous activity is sufficient. Animals were deprived of light either in adulthood only or from birth until the time of recording. We found that dark rearing from birth to 2 mo of age had no effect on the timing and extent of RF refinement as assessed with single unit extracellular recordings. Visual deprivation in adulthood also had no effect. Continuous dark rearing from birth into adulthood, however, resulted in a progressive loss of refinement, resulting in enlarged, asymmetric receptive fields and altered surround suppression in adulthood. Thus unlike in visual cortex, early visually driven activity is not necessary for refinement of receptive fields during development, but is required to maintain refined visual projections in adulthood. Because the map can refine normally in the dark, these results argue against a deprivation-induced delay in critical period closure, and suggest instead that early visual deprivation leaves target neurons more vulnerable to deprivation that continues after refinement.
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Affiliation(s)
- M M Carrasco
- Graduate Program in Neurobiology and Behavior, Department of Biology, Georgia State University, 24 Peachtree Center Ave., Atlanta, Georgia 30303, USA
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Barber JR, Razak KA, Fuzessery ZM. Can two streams of auditory information be processed simultaneously? Evidence from the gleaning bat Antrozous pallidus. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2003; 189:843-55. [PMID: 14564468 DOI: 10.1007/s00359-003-0463-6] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2003] [Accepted: 09/26/2003] [Indexed: 11/29/2022]
Abstract
A tenet of auditory scene analysis is that we can fully process only one stream of auditory information at a time. We tested this assumption in a gleaning bat, the pallid bat (Antrozous pallidus) because this bat uses echolocation for general orientation, and relies heavily on prey-generated sounds to detect and locate its prey. It may therefore encounter situations in which the echolocation and passive listening streams temporally overlap. Pallid bats were trained to a dual task in which they had to negotiate a wire array, using echolocation, and land on one of 15 speakers emitting a brief noise burst in order to obtain a food reward. They were forced to process both streams within a narrow 300 to 500 ms time window by having the noise burst triggered by the bats' initial echolocation pulses as it approached the wire array. Relative to single task controls, echolocation and passive sound localization performance was slightly, but significantly, degraded. The bats also increased echolocation interpulse intervals during the dual task, as though attempting to reduce temporal overlap between the signals. These results suggest that the bats, like humans, have difficulty in processing more than one stream of information at a time.
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Affiliation(s)
- J R Barber
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY 82071, USA
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Abstract
The current model of cortical processing of auditory spatial information is based on an orthogonal representation of frequency and binaural response properties, but how this arrangement leads to representation of space in the auditory cortex is unclear. This study describes the first evidence of a cortical substrate for the systematic representation of space in a region of primary auditory cortex of the pallid bat that subserves passive sound localization. The organizational feature of this region is a systematic shift in sensitivity to interaural intensity differences across the cortical surface, suggesting a topographic representation of horizontal space based on the distribution of activity within the neuron population.
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Affiliation(s)
- K A Razak
- Department of Zoology and Physiology, University of Wyoming, Laramie 82071, USA
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Abstract
The pallid bat uses passive listening at low frequencies to detect and locate terrestrial prey and reserves its high-frequency echolocation for general orientation. While hunting, this bat must attend to both streams of information. These streams are processed through two parallel, functionally specialized pathways that are segregated at the level of the inferior colliculus. This report describes functionally bimodal neurons in auditory cortex that receive converging input from these two pathways. Each brain stem pathway imposes its own suite of response properties on these cortical neurons. Consequently, the neurons are bimodally tuned to low and high frequencies, and respond selectively to both noise transients used in prey detection, and downward frequency modulation (FM) sweeps used in echolocation. A novel finding is that the monaural and binaural response properties of these neurons can change as a function of the sound presented. The majority of neurons appeared binaurally inhibited when presented with noise but monaural or binaurally facilitated when presented with the echolocation pulse. Consequently, their spatial sensitivity will change, depending on whether the bat is engaged in echolocation or passive listening. These results demonstrate that the response properties of single cortical neurons can change with behavioral context and suggest that they are capable of supporting more than one behavior.
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Affiliation(s)
- K A Razak
- Department of Zoology/Physiology, University of Wyoming, Laramie, Wyoming 82070, USA
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