1
|
Makkala P, Ruantip S, Buakeaw A, Chaiyo S, Khongchareonporn N. Integration of a hamper pad on test strips for improved sensitivity of carbendazim detection. Talanta 2024; 273:125911. [PMID: 38508129 DOI: 10.1016/j.talanta.2024.125911] [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: 11/22/2023] [Revised: 03/08/2024] [Accepted: 03/09/2024] [Indexed: 03/22/2024]
Abstract
Lateral flow immunoassays (LFIAs) are widely used to determine carbendazim (CBZ) residues in food products due to their advantages of low cost, ease and rapid use, on-site detection capability. However, conventional LFIAs have low detection sensitivity. Although improvements have been made to increase the sensitivity, it is not sufficient. Here, a hamper pad, polyvinyl alcohol coated on a nitrocellulose membrane, was integrated to enhance the sensitivity of LFIA for CBZ detection. The hamper pad was inserted between the conjugated and nitrocellulose pads to delay the flow rate, thereby increasing the possibility of the antibody and target analyte binding. This platform exhibited a fourfold sensitivity increase in CBZ detection compared with the conventional LFIA, and its limit of detection was 1.6 ng/mL. In addition, a single-step operation was successfully applied to detect CBZ in rice (white rice, brown rice, sticky rice, and paddy) and soybean samples, with acceptable recoveries of 93.6%-120.0%. This novel device was compared to the standard high-performance liquid chromatography method, which shows high accuracy with a Kappa coefficient of 0.91. Therefore, improved sensitivity with a rapid, simple, and inexpensive device could facilitate the detection of CBZ residues in agricultural products for on-field screening and improved user-friendliness.
Collapse
Affiliation(s)
- Pumnatthiga Makkala
- Program in Biotechnology, Faculty of Science, Chulalongkorn University, Bangkok, 10330, Thailand; The Institute of Biotechnology and Genetic Engineering, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Sirowan Ruantip
- The Institute of Biotechnology and Genetic Engineering, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Anumart Buakeaw
- The Institute of Biotechnology and Genetic Engineering, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Sudkate Chaiyo
- The Institute of Biotechnology and Genetic Engineering, Chulalongkorn University, Bangkok, 10330, Thailand; Center of Excellence for Food and Water Risk Analysis (FAWRA), Department of Veterinary Public Health, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand.
| | - Nanthika Khongchareonporn
- The Institute of Biotechnology and Genetic Engineering, Chulalongkorn University, Bangkok, 10330, Thailand; Center of Excellence for Food and Water Risk Analysis (FAWRA), Department of Veterinary Public Health, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand.
| |
Collapse
|
2
|
Greda K, Welna M, Szymczycha-Madeja A, Pohl P. Sensitive determination of Ag, Bi, Cd, Hg, Pb, Tl, and Zn by inductively coupled plasma optical emission spectrometry combined with the microplasma-assisted vapor generation. Talanta 2022; 249:123694. [PMID: 35738207 DOI: 10.1016/j.talanta.2022.123694] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [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: 03/31/2022] [Revised: 06/03/2022] [Accepted: 06/13/2022] [Indexed: 11/30/2022]
Abstract
A technique of vapor generation assisted by a microplasma was used for sample introduction into inductively coupled plasma optical emission spectrometry (ICP OES). Replacing a pneumatic nebulizer with a novel microplasma device improved the sensitivities of analytical signals for Ag, Bi, Cd, Pb, Tl, and Zn (by 2-13 times), as well as a concomitant reduction in their detection limits (DLs). Moreover, an outstanding improvement (30-fold) was achieved for Hg. The factors contributing to the boosted signal intensities were higher analyte fluxes and less water vapor produced by the microplasma system. The DLs of Ag, Bi, Cd, Hg, Pb, Tl, and Zn in microplasma-ICP OES were 0.4, 4, 0.06, 0.2, 2, 5, and 0.2 μg L-1, respectively, and the measurement precision was within the range of 0.7-2.4% (it was significantly improved as compared to that achievable with pneumatic nebulization). The proposed microplasma-assisted vapor generation eliminates the use of toxic reductants, e.g., sodium tetrahydridoborate, and it is characterized by higher resistance to matrix effects from transition metal ions (as compared to chemical vapor generation (CVG) and photochemical vapor generation (PVG)). To validate the trueness of the SAGD-ICP OES method, certified reference materials of lobster hepatopancreas (TORT-2), cormorant tissue (MODAS-4) as well as spiked tap water and seawater samples were analyzed to determine levels Cd and Hg. The standard additions method was used for calibration in both cases. Recoveries of the analytes in the case of the analysis of TORT-2 and MODAS-4 samples as well as the spiked tap water and seawater was within the range of 98-113%, which indicated that the developed sample introduction system can be successfully used for very sensitive determinations of selected hazardous elements in environmental samples.
Collapse
Affiliation(s)
- Krzysztof Greda
- Wroclaw University of Science and Technology, Faculty of Chemistry, Division of Analytical Chemistry and Chemical Metallurgy, Wybrzeze Stanislawa Wyspianskiego 27, 50-370, Wroclaw, Poland.
| | - Maja Welna
- Wroclaw University of Science and Technology, Faculty of Chemistry, Division of Analytical Chemistry and Chemical Metallurgy, Wybrzeze Stanislawa Wyspianskiego 27, 50-370, Wroclaw, Poland
| | - Anna Szymczycha-Madeja
- Wroclaw University of Science and Technology, Faculty of Chemistry, Division of Analytical Chemistry and Chemical Metallurgy, Wybrzeze Stanislawa Wyspianskiego 27, 50-370, Wroclaw, Poland
| | - Pawel Pohl
- Wroclaw University of Science and Technology, Faculty of Chemistry, Division of Analytical Chemistry and Chemical Metallurgy, Wybrzeze Stanislawa Wyspianskiego 27, 50-370, Wroclaw, Poland
| |
Collapse
|
3
|
Sakhaii P, Bohorc B, Schliedermann U, Berchtold H, Bermel W. Mirror symmetric broadband homodecoupled perfect echo spectroscopy. J Magn Reson 2020; 315:106753. [PMID: 32464370 DOI: 10.1016/j.jmr.2020.106753] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 05/09/2020] [Accepted: 05/13/2020] [Indexed: 06/11/2023]
Abstract
A new experiment for recording phase sensitive ω1-broadband homodecoupled TOCSY spectra is presented. The method is an extension of the already existing perfect echo (PE) filter, proposed to sample t1 chemical shift under sustained homodecoupling. The modification is made by attaching a time reversed perfect echo filter to a regular perfect echo scheme. Thus it becomes possible to acquire for longer t1 acquisition times without compromising the quality of homodecoupling. The mirror symmetric double perfect echo is implemented into the evolution period of a TOCSY experiment. A spin lock pulse purges undesired dispersive antiphase components at the end of the central t1 evolution period. Pure absorptive lineshapes with reduced proton spin multiplicities are obtained. The approach can be used in conjunction with real or constant time chemical shift evolution. In case of compounds with reduced T2 relaxation time, the real time approach is advisable, where the echo delays are an extension of the t1 evolution period. In this way, an unnecessary loss due to T2 relaxation is avoided. Using the pulse sequence in constant time mode at high t1max values gives ω1-homodecoupled TOCSY spectra without a significant dependence of the transfer amplitude on J. All experiments were carried out using non uniform sampling to decrease the measurement time. Experimental setup, advantages and limitations are discussed.
Collapse
Affiliation(s)
- Peyman Sakhaii
- NMR Laboratory of SANOFI, TIDES Analytical Sciences / German NMR Platform Industriepark Hoechst, Building G849, D-65926 Frankfurt/Main, Germany.
| | - Bojan Bohorc
- NMR Laboratory of SANOFI, TIDES Analytical Sciences / German NMR Platform Industriepark Hoechst, Building G849, D-65926 Frankfurt/Main, Germany.
| | - Uwe Schliedermann
- NMR Laboratory of SANOFI, TIDES Analytical Sciences / German NMR Platform Industriepark Hoechst, Building G849, D-65926 Frankfurt/Main, Germany.
| | - Harald Berchtold
- NMR Laboratory of SANOFI, TIDES Analytical Sciences / German NMR Platform Industriepark Hoechst, Building G849, D-65926 Frankfurt/Main, Germany.
| | - Wolfgang Bermel
- Bruker BioSpin GmbH, Silberstreifen, D-76287 Rheinstetten, Germany.
| |
Collapse
|
4
|
Shirshahi V, Tabatabaei SN, Hatamie S, Saber R. Photothermal enhancement in sensitivity of lateral flow assays for detection of E-coli O157:H7. Colloids Surf B Biointerfaces 2019; 186:110721. [PMID: 31855687 DOI: 10.1016/j.colsurfb.2019.110721] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [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: 08/13/2019] [Revised: 11/27/2019] [Accepted: 12/10/2019] [Indexed: 11/30/2022]
Abstract
Lateral flow immunoassay (LFA) is a well-known point-of-care technology for the detection of various analytes. However, low sensitivity and lack of quantitative results are some of its critical drawbacks. Here we report a photothermal enhanced lateral flow sensor on the basis of the photothermal properties of reduced graphene oxide (rGO) for the detection of E-coli O157:H7 as a model pathogen. The calibration curve of the photothermal method exhibited a linear range from 5 × 10⁵ to 5 × 10⁷ CFU/ml with a correlation coefficient of R2 = 0.96 and a regression equation of y = 8.1x-43 for standard bacteria solutions in phosphate buffer. The limit of detection was ∼5 × 10⁵ CFU/ml for standard bacteria solutions, which was a 10-fold enhancement in sensitivity compared to the qualitative results. Specificity experiments showed that the photothermal method can only detect the target bacteria among 6 types of bacteria strains. It was confirmed that the developed technique could be a highly potential method for the rapid detection field because it can provide fast quantitative results with improved sensitivity.
Collapse
Affiliation(s)
- Vahid Shirshahi
- Department of Medical Nanotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran; School of Medicine, Shahroud University of Medical Sciences, Shahroud, Iran
| | - Seyed Nasrollah Tabatabaei
- Department of Medical Nanotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | | | - Reza Saber
- Department of Medical Nanotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran; Research Center of Science and Technology in Medicine, RCSTIM, Tehran University of Medical Sciences, Tehran, Iran.
| |
Collapse
|
5
|
Zhan C, Zeng Q, Chen J, Lin Y, Chen Z. PE-SERF: A sensitivity-improved experiment to measure J HH in crowded spectra. J Magn Reson 2019; 308:106590. [PMID: 31513964 DOI: 10.1016/j.jmr.2019.106590] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 08/22/2019] [Accepted: 09/02/2019] [Indexed: 06/10/2023]
Abstract
Aiming at facilitating the analysis of molecular structure, the gradient-encoded selective refocusing methods (G-SERF) and a great number of its variants for measuring proton-proton coupling constants have been proposed. However, the sensitivity is an issue in the 2D gradient-encoded experiments, because the signal intensity is determined by the slice thickness of the sample that depends on encoding gradient and the bandwidth of selective pulses which is limited by the smallest chemical shift difference of any two coupled protons. Here, we present a method dubbed PE-SERF (perfect echo selective refocusing) which can determine all JHH values involving a selected proton with improved sensitivity compared to original G-SERF experiment. The modules of perfect echo involving selective pulses and gradient-encoded selective refocusing are combined in the method, so that the unwanted J couplings arising from coupled spin pairs in the same sample slice would be nullified. In this way, instead of single proton, a pair of coupled protons is allowed to share a sample slice, and thus the slice thickness can be increased and the spectral sensitivity can be improved. The performance of the method is demonstrated by experiments on quinine and strychnine.
Collapse
Affiliation(s)
- Chaoqun Zhan
- Department of Electronic Science, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, State Key Laboratory for Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen 361005, China
| | - Qing Zeng
- Department of Electronic Science, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, State Key Laboratory for Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen 361005, China
| | - Jinyong Chen
- Department of Electronic Science, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, State Key Laboratory for Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen 361005, China
| | - Yanqin Lin
- Department of Electronic Science, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, State Key Laboratory for Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen 361005, China; Shenzhen Research Institute of Xiamen University, Shenzhen 518057, China.
| | - Zhong Chen
- Department of Electronic Science, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, State Key Laboratory for Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen 361005, China
| |
Collapse
|
6
|
Shao H, Wen X, Ding Y, Hong X, Zhao H. Colorimetric determination of copper(II) by using branched-polyethylenimine droplet evaporation on a superhydrophilic-superhydrophobic micropatterned surface. Mikrochim Acta 2019; 186:701. [PMID: 31620903 DOI: 10.1007/s00604-019-3805-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 09/08/2019] [Indexed: 12/31/2022]
Abstract
A colorimetric method is described for the determination of Cu(II). It is based on branched polyethylenimine (BPEI) droplet evaporation on a superhydrophilic-superhydrophobic polystyrene micropatterned surface. Exposure to Cu(II) leads to a color change from colorless to light blue and dark blue. The micropatterned surface was fabricated via combining electrospinning with oxygen plasma and served as a detection substrate. Analysis requires only a single drop of blood. The method has a linear response in the 5.0 μM to 2.5 mM Cu(II) concentration range which is within the physiological range (15.7 ∼ 23.6 μM). Compared to an assay in solution, the detection limit is decreased from 386 nM to 89 nM. Excellent selectivity over other metal ions and anions was achieved. Graphical abstract A rapid and sensitive colorimetric detection platform for Cu(II) was fabricated by using branched-polyethylenimine droplet evaporation on a superhydrophilic-superhydrophobic micropatterned surface. Only a single drop of blood was needed for the analysis. The sensitivity was improved about 4.3 times.
Collapse
Affiliation(s)
- Hong Shao
- Key Laboratory of UV-Emitting Materials and Technology, Ministry of Education, Northeast Normal University, Changchun, Jilin, 130024, People's Republic of China
| | - Xiaokun Wen
- Key Laboratory of UV-Emitting Materials and Technology, Ministry of Education, Northeast Normal University, Changchun, Jilin, 130024, People's Republic of China
| | - Yadan Ding
- Key Laboratory of UV-Emitting Materials and Technology, Ministry of Education, Northeast Normal University, Changchun, Jilin, 130024, People's Republic of China
| | - Xia Hong
- Key Laboratory of UV-Emitting Materials and Technology, Ministry of Education, Northeast Normal University, Changchun, Jilin, 130024, People's Republic of China.
| | - Huiying Zhao
- Department of Basic Medicine, Gerontology Department of First Bethune Hospital, Jilin University, Changchun, Jilin, 130021, People's Republic of China.
| |
Collapse
|
7
|
Crego AL, Mateos M, Nozal L. Recent contributions for improving sensitivity in chiral CE. Electrophoresis 2017; 39:67-81. [PMID: 28960403 DOI: 10.1002/elps.201700293] [Citation(s) in RCA: 9] [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: 07/21/2017] [Revised: 09/14/2017] [Accepted: 09/14/2017] [Indexed: 01/02/2023]
Abstract
The flexibility and versatility of the chiral CE are unrivaled and the same instrumentation can be used to separate a diverse range of analytes, both large and small molecules, whether charged or uncharged. However, one of the disadvantages is generally thought to be the poor sensitivity of ultraviolet (UV) detection, which is the most popular among CE detectors. This review focuses on methodologies and applications regarding improvements of sensitivity in chiral CE published in the last 2 years (June 2015 until May 2017). This contribution continues to update this series of biannual reviews, first published in Electrophoresis in 2006. The main body of the review brings a survey of publications organized according to different approaches to detect a low amount of analytes, either by sample treatment procedures or by in-capillary sample preconcentration techniques, both using UV detection, or even by employing detection systems more sensitive than UV absorption, such as LIF or MS. This review provides comprehensive tables listing the new approaches in sensitive chiral CE with categorizing by the fundamental mechanism to enhance the sensitivity, which provide relevant information on the strategies employed. The concluding remarks in the final part of the review evaluate present state of art and the trends for sensitivity enhancement in chiral CE.
Collapse
Affiliation(s)
- Antonio Luis Crego
- Department of Analytical Chemistry, Physical Chemistry, and Chemical Engineering, Faculty of Biology, Environmental Sciences, and Chemistry, University of Alcalá, Madrid, Spain
| | - María Mateos
- Institute of Applied Chemistry and Biotechnology, University of Alcalá, Madrid, Spain
| | - Leonor Nozal
- Institute of Applied Chemistry and Biotechnology, University of Alcalá, Madrid, Spain
| |
Collapse
|
8
|
Castañar L, Saurí J, Nolis P, Virgili A, Parella T. Implementing homo- and heterodecoupling in region-selective HSQMBC experiments. J Magn Reson 2014; 238:63-69. [PMID: 24316187 DOI: 10.1016/j.jmr.2013.10.022] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [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: 09/21/2013] [Revised: 10/27/2013] [Accepted: 10/28/2013] [Indexed: 06/02/2023]
Abstract
An NMR method to enhance the sensitivity and resolution in band-selective long-range heteronuclear correlation spectra is proposed. The excellent in-phase nature of the selHSQMBC experiment allows that homonuclear and/or heteronuclear decoupling can be achieved in the detected dimension of a 2D multiple-bond correlation map, obtaining simplified cross-peaks without their characteristic fine J multiplet structure. The experimental result is a resolution improvement while the highest sensitivity is also achieved. Specifically, it is shown that the (1)H-homodecoupled band-selective (HOBS) HSQMBC experiment represents a new way to measure heteronuclear coupling constants from the simplified in-phase doublets generated along the detected dimension.
Collapse
Affiliation(s)
- Laura Castañar
- Servei de Ressonància Magnètica Nuclear and Departament de Química, Universitat Autònoma de Barcelona, E-08193 Bellaterra (Catalonia), Spain
| | - Josep Saurí
- Servei de Ressonància Magnètica Nuclear and Departament de Química, Universitat Autònoma de Barcelona, E-08193 Bellaterra (Catalonia), Spain
| | - Pau Nolis
- Servei de Ressonància Magnètica Nuclear and Departament de Química, Universitat Autònoma de Barcelona, E-08193 Bellaterra (Catalonia), Spain
| | - Albert Virgili
- Servei de Ressonància Magnètica Nuclear and Departament de Química, Universitat Autònoma de Barcelona, E-08193 Bellaterra (Catalonia), Spain
| | - Teodor Parella
- Servei de Ressonància Magnètica Nuclear and Departament de Química, Universitat Autònoma de Barcelona, E-08193 Bellaterra (Catalonia), Spain.
| |
Collapse
|