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Ma H, Hua Y, Zhu C, Hou Z, Zhao B, Pu Y, Cai Z, Zhang L, Li T, Xu J. Reaction Kinetics at PDMS-E Emulsion Droplet-Gelatin Interface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:894-900. [PMID: 30607955 DOI: 10.1021/acs.langmuir.8b03633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
In this work, interfacial reaction kinetics between α-[3-(2,3-epoxypropoxy)propyl]-ω-butyl-polydimethylsiloxane emulsion droplets with different sizes and gelatin was studied. The results of amino conversion rate determination show that the reaction proceeded in two steps. Fluorescence spectra analysis indicates that step 1 (0-2 h) should be the adsorption of gelatin on droplet surface. In step 2 (2-13 h), amino conversion rate increased rapidly. The reaction rate in step 2 ( k2) was obtained by using the 2nd-order approach to model the grafting reaction kinetics. The quantitative relationships among amino conversion rate, droplet size, the concentration of surfactant, reaction temperature, and time were described by linear regression models in given ranges of conditions in step 2. Thermodynamic analysis indicates that the interfacial reaction is an endothermic reaction. After 13 h, the reaction was almost stopped.
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Affiliation(s)
- Huijun Ma
- Shandong Provincial Key Laboratory of Molecular Engineering, School of Chemistry and Pharmaceutical Engineering; College of Mathematics and Statistics , Qilu University of Technology (Shandong Academy of Sciences) , Jinan 250353 , P. R. China
| | - Yuai Hua
- Shandong Provincial Key Laboratory of Molecular Engineering, School of Chemistry and Pharmaceutical Engineering; College of Mathematics and Statistics , Qilu University of Technology (Shandong Academy of Sciences) , Jinan 250353 , P. R. China
| | - Cong Zhu
- Shandong Provincial Key Laboratory of Molecular Engineering, School of Chemistry and Pharmaceutical Engineering; College of Mathematics and Statistics , Qilu University of Technology (Shandong Academy of Sciences) , Jinan 250353 , P. R. China
| | - Zhaosheng Hou
- College of Chemistry, Chemical Engineering and Materials Science , Shandong Normal University , Jinan 250100 , P. R. China
| | - Bo Zhao
- Shandong Provincial Key Laboratory of Molecular Engineering, School of Chemistry and Pharmaceutical Engineering; College of Mathematics and Statistics , Qilu University of Technology (Shandong Academy of Sciences) , Jinan 250353 , P. R. China
| | - Yongli Pu
- Shandong Provincial Key Laboratory of Molecular Engineering, School of Chemistry and Pharmaceutical Engineering; College of Mathematics and Statistics , Qilu University of Technology (Shandong Academy of Sciences) , Jinan 250353 , P. R. China
| | - Zhaoning Cai
- Shandong Provincial Key Laboratory of Molecular Engineering, School of Chemistry and Pharmaceutical Engineering; College of Mathematics and Statistics , Qilu University of Technology (Shandong Academy of Sciences) , Jinan 250353 , P. R. China
| | - Liangli Zhang
- Shandong Provincial Key Laboratory of Molecular Engineering, School of Chemistry and Pharmaceutical Engineering; College of Mathematics and Statistics , Qilu University of Technology (Shandong Academy of Sciences) , Jinan 250353 , P. R. China
| | - Tianduo Li
- Shandong Provincial Key Laboratory of Molecular Engineering, School of Chemistry and Pharmaceutical Engineering; College of Mathematics and Statistics , Qilu University of Technology (Shandong Academy of Sciences) , Jinan 250353 , P. R. China
| | - Jing Xu
- Shandong Provincial Key Laboratory of Molecular Engineering, School of Chemistry and Pharmaceutical Engineering; College of Mathematics and Statistics , Qilu University of Technology (Shandong Academy of Sciences) , Jinan 250353 , P. R. China
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Kumada Y, Ootsuka T, Asada M, Yoshizuka S, Chiyama M, Sakane M, Fida HM, Sawada K, Okumura K, Kishimoto M. Identification and characterization of peptide fragments for the direct and site-specific immobilization of functional proteins onto the surface of silicon nitride. J Biotechnol 2014; 184:103-10. [DOI: 10.1016/j.jbiotec.2014.04.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Revised: 04/07/2014] [Accepted: 04/11/2014] [Indexed: 11/25/2022]
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3
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Dorvel B, Reddy B, Bashir R. Effect of biointerfacing linker chemistries on the sensitivity of silicon nanowires for protein detection. Anal Chem 2013; 85:9493-500. [PMID: 24040958 DOI: 10.1021/ac400955f] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Point-of-care diagnostics show promise in removing reliance on centralized lab testing facilities and may help increase both the survival rate for infectious diseases as well as monitoring of chronic illnesses. CMOS compatible diagnostic platforms are currently being considered as possible solutions as they can be easily miniaturized and can be cost-effective. Top-down fabricated silicon nanowires are a CMOS-compatible technology which have demonstrated high sensitivities in detecting biological analytes, such as proteins, DNA, and RNA. However, the reported response of nanowires to these analytes has varied widely since several different functionalization protocols have been attempted with little characterization and comparison. Here we report protocols for fabrication and functionalization of silicon nanowires which yield highly stable nanowires in aqueous solutions and limits of detection to ∼1 pg/mL of the model protein used in the study. A thorough characterization was done into optimizing the release of the silicon nanowires using combined dry and wet etch techniques, which yielded nanowires that could be directly compared to increase output statistics. Moreover, a range of different linker chemistries were tried for reacting the primary antibody, and its response to target and nonspecific antigens, with polyethylene glycol based linker BS(PEG)5 providing the best response. Consequently, this chemistry was used to characterize different oxide thicknesses and their responses to the mouse IgG antigen, which with the smallest oxide thickness yielded 0.1-1 pg/mL limits of detection and a dynamic range over 3 orders of magnitude.
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Affiliation(s)
- Brian Dorvel
- Center for Biophysics and Computational Biology, University of Illinois at Urbana-Champaign , Urbana, Illinois 61801, United States
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4
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Sharon E, Liu X, Freeman R, Yehezkeli O, Willner I. Label-Free Analysis of Thrombin or Hg2+Ions by Nucleic Acid-Functionalized Graphene Oxide Matrices Assembled on Field-Effect Transistors. ELECTROANAL 2012. [DOI: 10.1002/elan.201200581] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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5
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Spijkman MJ, Myny K, Smits ECP, Heremans P, Blom PWM, de Leeuw DM. Dual-gate thin-film transistors, integrated circuits and sensors. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2011; 23:3231-3242. [PMID: 21671446 DOI: 10.1002/adma.201101493] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2011] [Indexed: 05/30/2023]
Abstract
The first dual-gate thin-film transistor (DGTFT) was reported in 1981 with CdSe as the semiconductor. Other TFT technologies such as a-Si:H and organic semiconductors have led to additional ways of making DGTFTs. DGTFTs contain a second gate dielectric with a second gate positioned opposite of the first gate. The main advantage is that the threshold voltage can be set as a function of the applied second gate bias. The shift depends on the ratio of the capacitances of the two gate dielectrics. Here we review the fast growing field of DGTFTs. We summarize the reported operational mechanisms, and the application in logic gates and integrated circuits. The second emerging application of DGTFTs is sensitivity enhancement of existing ion-sensitive field-effect transistors (ISFET). The reported sensing mechanism is discussed and an outlook is presented.
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Affiliation(s)
- Mark-Jan Spijkman
- Philips Research Laboratories, High Tech Campus, AE Eindhoven, The Netherlands.
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6
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Mohammed MI, Desmulliez MPY. Lab-on-a-chip based immunosensor principles and technologies for the detection of cardiac biomarkers: a review. LAB ON A CHIP 2011; 11:569-95. [PMID: 21180774 DOI: 10.1039/c0lc00204f] [Citation(s) in RCA: 174] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
This review examines the current state of the art lab-on-a-chip and microfluidic based biosensor technologies used in the detection of cardiac biomarkers. The determination and quantification of blood based, cardiac biomarkers are crucial in the triage and management of a range of cardiac related conditions, where time delay has a major impact on short and longer-term outcomes of a patient. The design and manufacturing of biomarker detection systems are multi-disciplinary in nature and require researchers to have knowledge of both life sciences and engineering for the full potential of this field to be realised. This review will therefore provide a comprehensive overview of chip based immunosensing technology as applied to cardiac biomarker detection, while discussing the potential suitability and limitations of each configuration for incorporation within a clinical diagnostics device suitable for point-of-care applications.
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Affiliation(s)
- Mazher-Iqbal Mohammed
- Heriot-Watt University, MicroSystems Engineering Centre (MISEC), School of Engineering & Physical Sciences, Earl Mountbatten Building, Edinburgh, Scotland
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7
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Jiayu W, Xiong W, Jiping L, Wensen L, Ming X, Linna L, Jing X, Haiying W, Hongwei G. A rapid method for detection of PrP by surface plasmon resonance (SPR). Arch Virol 2009; 154:1901-8. [DOI: 10.1007/s00705-009-0532-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2009] [Accepted: 09/29/2009] [Indexed: 12/21/2022]
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8
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Ion-sensitive field-effect transistor for biological sensing. SENSORS 2009; 9:7111-31. [PMID: 22423205 PMCID: PMC3290489 DOI: 10.3390/s90907111] [Citation(s) in RCA: 163] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/04/2009] [Revised: 08/27/2009] [Accepted: 08/31/2009] [Indexed: 12/12/2022]
Abstract
In recent years there has been great progress in applying FET-type biosensors for highly sensitive biological detection. Among them, the ISFET (ion-sensitive field-effect transistor) is one of the most intriguing approaches in electrical biosensing technology. Here, we review some of the main advances in this field over the past few years, explore its application prospects, and discuss the main issues, approaches, and challenges, with the aim of stimulating a broader interest in developing ISFET-based biosensors and extending their applications for reliable and sensitive analysis of various biomolecules such as DNA, proteins, enzymes, and cells.
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Sharon E, Freeman R, Tel-Vered R, Willner I. Impedimetric or Ion-Sensitive Field-Effect Transistor (ISFET) Aptasensors Based on the Self-Assembly of Au Nanoparticle-Functionalized Supramolecular Aptamer Nanostructures. ELECTROANAL 2009. [DOI: 10.1002/elan.200804565] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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10
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Over-the-Counter Biosensors: Past, Present, and Future. SENSORS 2008; 8:5535-5559. [PMID: 27873829 PMCID: PMC3705519 DOI: 10.3390/s8095535] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2008] [Revised: 08/28/2008] [Accepted: 09/03/2008] [Indexed: 11/17/2022]
Abstract
The demand for specific, low cost, rapid, sensitive and easy detection of biomolecules is huge. A well-known example is the glucose meters used by diabetics to monitor their blood glucose levels. Nowadays, a vast majority of the glucose meters are based on electrochemical biosensor technology. The inherent small size and simple construction of the electrochemical transducer and instrument are ideally suited for point-of-care biosensing. Besides glucose, a wide variety of electrochemical biosensors have been developed for the measurements of some other key metabolites, proteins, and nucleic acids. Nevertheless, unlike the glucose meters, limited success has been achieved for the commercialization of the protein and nucleic acid biosensors. In this review article, key technologies on the electrochemical detection of key metabolites, proteins, and DNAs are discussed in detail, with particular emphasis on those that are compatible to home-use setting. Moreover, emerging technologies of lab-on-a-chip microdevices and nanosensors (i.e., silicon and carbon nanotube field-effect sensors) offer opportunities for the construction of new generation biosensors with much better performances. Together with the continuous innovations in the basic components of biosensors (i.e., transducers, biorecognition molecules, immobilization and signal transduction schemes), consumers could soon buy different kinds of biosensing devices in the pharmacy stores.
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11
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McKinley BA. ISFET and fiber optic sensor technologies: in vivo experience for critical care monitoring. Chem Rev 2008; 108:826-44. [PMID: 18179258 DOI: 10.1021/cr068120y] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Bruce A McKinley
- Department of Surgery, The Methodist Hospital, Houston, TX 77030, USA.
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KAMAHORI M, ISHIGE Y, SHIMODA M. Enzyme Immunoassay Using a Reusable Extended-gate Field-Effect-Transistor Sensor with a Ferrocenylalkanethiol-modified Gold Electrode. ANAL SCI 2008; 24:1073-9. [DOI: 10.2116/analsci.24.1073] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
| | - Yu ISHIGE
- Central Research Laboratory, Hitachi, Ltd
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13
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Freeman R, Elbaz J, Gill R, Zayats M, Willner I. Analysis of Dopamine and Tyrosinase Activity on Ion-Sensitive Field-Effect Transistor (ISFET) Devices. Chemistry 2007; 13:7288-93. [PMID: 17685382 DOI: 10.1002/chem.200700734] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Dopamine (1) and tyrosinase (TR) activities were analyzed by using chemically modified ion-sensitive field-effect transistor (ISFET) devices. In one configuration, a phenylboronic acid functionalized ISFET was used to analyze 1 or TR. The formation of the boronate-1 complex on the surface of the gate altered the electrical potential associated with the gate, and thus enabled 1 to be analyzed with a detection limit of 7x10(-5) M. Similarly, the TR-induced formation of 1, and its association with the boronic acid ligand allowed a quantitative assay of TR to be performed. In another configuration, the surface of the ISFET gate was modified with tyramine or 1 to form functional surfaces for analyzing TR activities. The TR-induced oxidation of the tyramine- or 1-functionalized ISFETs resulted in the formation of the redox-active dopaquinone units. The control of the gate potential by the redox-active dopaquinone units allowed a quantitative assay of TR to be performed. The dopaquinone-functionalized ISFETs could be regenerated to give the 1-modified sensing devices by treatment with ascorbic acid.
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Affiliation(s)
- Ronit Freeman
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
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Koncki R. Recent developments in potentiometric biosensors for biomedical analysis. Anal Chim Acta 2007; 599:7-15. [PMID: 17765058 DOI: 10.1016/j.aca.2007.08.003] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2007] [Revised: 07/30/2007] [Accepted: 08/02/2007] [Indexed: 11/18/2022]
Abstract
A large variety of potentiometric biosensors is developed using biocatalytic and bioaffinity-based biosensing schemes. However, only few of them could be applied for the biomedical analysis. The most promising are those for the detection of main products of protein metabolism, namely urea and creatinine. A novel group of potentiometric biosensors is constituted by bioaffinity-based devices that could be used for immunoassays or genoanalysis. This paper reviews the recent trends in these fields as well as discusses advantages, limitations and pitfalls of the developed biosensors. Some potentiometric biosensors useful for real biomedical analysis are reported in detail.
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Affiliation(s)
- Robert Koncki
- University of Warsaw, Department of Chemistry, Pasteura 1, 02-093 Warsaw, Poland.
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Kamahori M, Ishige Y, Shimoda M. A novel enzyme immunoassay based on potentiometric measurement of molecular adsorption events by an extended-gate field-effect transistor sensor. Biosens Bioelectron 2007; 22:3080-5. [PMID: 17324568 DOI: 10.1016/j.bios.2007.01.011] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2006] [Revised: 11/20/2006] [Accepted: 01/10/2007] [Indexed: 11/29/2022]
Abstract
We developed a novel enzyme immunoassay based on a potentiometric measurement of molecular adsorption events by using an extended-gate field-effect transistor (FET) sensor. The adsorbing rate of a thiol compound on a gold surface was found to depend on the concentration of the compound. To construct an electrochemical enzyme immunoassay system by using the sensor, the enzyme chemistry of acetylcholinesterase (AChE) to generate a thiol compound was used and combined with the enzyme-linked immunosorbent assays (ELISA). After the AChE-catalyzed reaction, the amount of the antigen was obtained by detecting the adsorbing rate of the generated thiol compound on the gold electrode using the FET sensor. The measurement stability was also found to improve when a high frequency voltage of 10 kHz or more was superimposed to the reference electrode. The signal corresponding to a range between 1 and 250 pg/mL of Interleukin 1 beta was obtained by the FET sensor when a voltage of 1 MHz was superimposed onto the reference electrode. The FET sensor based ELISA used in this measurement technique can successfully detect Interleukin 1 beta at concentrations as low as 1 pg/mL.
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Affiliation(s)
- Masao Kamahori
- Central Research Laboratory, Hitachi, Ltd., 1-280 Higashi-Koigakubo, Kokubunji-shi, Tokyo 185-8601, Japan.
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Sergeev M, Costantino S, Wiseman PW. Measurement of monomer-oligomer distributions via fluorescence moment image analysis. Biophys J 2006; 91:3884-96. [PMID: 16935950 PMCID: PMC1630488 DOI: 10.1529/biophysj.106.091181] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2006] [Accepted: 08/11/2006] [Indexed: 11/18/2022] Open
Abstract
We present higher-order moment analysis of fluorescence intensity fluctuations from individual laser scanning microscopy images applied to study monomer-oligomer distributions. We demonstrate that the number densities and brightness ratios of a mixed population of monomers and oligomers can be determined by analyzing higher-order moments of the fluorescence intensity fluctuations from individual images for specific ranges of densities and particle brightness ratios. Computer simulations and experiments with fluorescent microspheres and cells were performed to illustrate the detection limits and accuracy of this statistical approach. The simulation results show that the concentration of the dimer or oligomer population should be less than or equal to the monomeric concentration for the method to provide accurate results, and that the upper density detection limit of the population of monomers is one order-of-magnitude higher than the concentration of the oligomers. We implemented this technique to resolve two populations of fluorescent microspheres with different brightness ratios and we also applied the moment-analysis method to examine the distribution of aggregation states of PDGF-beta receptors in human fibroblast cells. The method was able to resolve a tetrameric population of the PDGF-beta receptors relative to the background distribution of nonspecifically bound fluorophore.
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Affiliation(s)
- Mikhail Sergeev
- Department of Physics, and Department of Chemistry, McGill University, Montreal, Quebec, Canada
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Karir T, Hassan PA, Kulshreshtha SK, Samuel G, Sivaprasad N, Meera V. Surface Modification of Polystyrene Using Polyaniline Nanostructures for Biomolecule Adhesion in Radioimmunoassays. Anal Chem 2006; 78:3577-82. [PMID: 16737210 DOI: 10.1021/ac052032g] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The selection of an appropriate surface as a solid phase for coupling antibodies is a critical step in the development of solid-phase immunoassays. Availability of a new method of preactivating the surface of polystyrene tubes with a layer of another polymer for enhanced immobilization of antibodies seems to be promising. In this paper, we report the activation of a polystyrene surface using a layer of polyaniline and its effect on immobilizing antibodies for use as a solid phase in a T3 immunoassay. The modified surface on the polystyrene was characterized by optical absorption, X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). The modified tubes were coated with antibody and evaluated for their performance in the assay and validated for radioimmunoassay of T3. AFM images of the modified surface showed an enhancement in the surface roughness (Ra of 20.2 nm), as compared to an unmodified surface (Ra of 6 nm), allowing more adsorption of antibodies to the surface. XPS revealed the presence of N (binding energy approximately 400 eV) on the modified surface, which could help the antibody molecules to bind to these preactivated (modified) tubes. The modified tubes, when coated with antibody, not only showed an increase in the binding with the radioiodinated tracer but also improved the precision of coating the antibody. The present method of activating polystyrene surfaces is simple, does not involve severe chemical treatment, and may have wide applicability to functionalize other supports for immobilizing biomolecules.
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Affiliation(s)
- Tarveen Karir
- Radiopharmaceuticals Program, Board of Radiation and Isotope Technology, Department of Atomic Energy, Navi Mumbai, India
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Hromadová M, Salmain M, Fischer-Durand N, Pospísil L, Jaouen G. Electrochemical microbead-based immunoassay using an (eta5-cyclopentadienyl)tricarbonylmanganese redox marker bound to bovine serum albumin. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2006; 22:506-11. [PMID: 16378466 DOI: 10.1021/la052188b] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
A first example of the solid-phase immunoassay of a high-weight antigen bovine serum albumin (BSA) using an (eta(5)-cyclopentadienyl)tricarbonylmanganese (cymantrene) redox probe is presented. The electrochemical detection is based on the impedance measurements of a one-electron reversible reduction of the organometallic probe. The microbead-based immunoassay is discussed for two types of microbeads with different diameters (2.5 and 90 microm) and capabilities to bind the immunoglobulins (2.4 and 10 microg/mg of beads). The use of larger agarose microbeads allows the formation of an antigen-antibody complex at the surface of microbeads directly dispersed in the analyzed solution. No additional separation step is necessary for the electrochemical competitive immunoassay analysis of BSA. The presence of agarose beads in the analyzed solution has no effect on the electrochemical signal from labeled BSA released from the antigen-antibody complex.
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Affiliation(s)
- Magdaléna Hromadová
- J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejskova 3, 182 23 Prague, Czech Republic
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Bead injection with a simple flow-injection system: an economical alternative for trace analysis. Trends Analyt Chem 2004. [DOI: 10.1016/j.trac.2004.06.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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