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Development of a voltammetric assay, using screen-printed electrodes, for clonazepam and its application to beverage and serum samples. Talanta 2016; 147:510-5. [DOI: 10.1016/j.talanta.2015.10.032] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2015] [Revised: 10/12/2015] [Accepted: 10/13/2015] [Indexed: 11/22/2022]
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Sağlam Ş, Üzer A, Tekdemir Y, Erçağ E, Apak R. Electrochemical sensor for nitroaromatic type energetic materials using gold nanoparticles/poly(o-phenylenediamine–aniline) film modified glassy carbon electrode. Talanta 2015; 139:181-8. [DOI: 10.1016/j.talanta.2015.02.059] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Revised: 02/23/2015] [Accepted: 02/28/2015] [Indexed: 11/28/2022]
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Trammell SA, Zabetakis D, Moore M, Verbarg J, Stenger DA. Square wave voltammetry of TNT at gold electrodes modified with self-assembled monolayers containing aromatic structures. PLoS One 2014; 9:e115966. [PMID: 25549081 PMCID: PMC4280194 DOI: 10.1371/journal.pone.0115966] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Accepted: 12/01/2014] [Indexed: 11/21/2022] Open
Abstract
Square wave voltammetry for the reduction of 2,4,6-trinitrotoluene (TNT) was measured in 100 mM potassium phosphate buffer (pH 8) at gold electrodes modified with self-assembled monolayers (SAMs) containing either an alkane thiol or aromatic ring thiol structures. At 15 Hz, the electrochemical sensitivity (µA/ppm) was similar for all SAMs tested. However, at 60 Hz, the SAMs containing aromatic structures had a greater sensitivity than the alkane thiol SAM. In fact, the alkane thiol SAM had a decrease in sensitivity at the higher frequency. When comparing the electrochemical response between simulations and experimental data, a general trend was observed in which most of the SAMs had similar heterogeneous rate constants within experimental error for the reduction of TNT. This most likely describes a rate limiting step for the reduction of TNT. However, in the case of the alkane SAM at higher frequency, the decrease in sensitivity suggests that the rate limiting step in this case may be electron tunneling through the SAM. Our results show that SAMs containing aromatic rings increased the sensitivity for the reduction of TNT when higher frequencies were employed and at the same time suppressed the electrochemical reduction of dissolved oxygen.
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Affiliation(s)
- Scott A Trammell
- Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, Washington, DC, United States of America
| | - Dan Zabetakis
- Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, Washington, DC, United States of America
| | - Martin Moore
- Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, Washington, DC, United States of America
| | - Jasenka Verbarg
- Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, Washington, DC, United States of America
| | - David A Stenger
- Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, Washington, DC, United States of America
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Yuan CX, Fan YR, Tao-Zhang, Guo HX, Zhang JX, Wang YL, Shan DL, Lu XQ. A new electrochemical sensor of nitro aromatic compound based on three-dimensional porous Pt–Pd nanoparticles supported by graphene–multiwalled carbon nanotube composite. Biosens Bioelectron 2014; 58:85-91. [DOI: 10.1016/j.bios.2014.01.041] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 01/20/2014] [Accepted: 01/23/2014] [Indexed: 11/24/2022]
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Ma Y, Huang S, Deng M, Wang L. White upconversion luminescence nanocrystals for the simultaneous and selective detection of 2,4,6-trinitrotoluene and 2,4,6-trinitrophenol. ACS APPLIED MATERIALS & INTERFACES 2014; 6:7790-7796. [PMID: 24734988 DOI: 10.1021/am501053n] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
A highly water stable and strong upconversion (UC) luminescence NaYF4@PSI-NH nanosensor for the simultaneous and selective detection of 2,4,6-trinitrotoluene (TNT) and 2,4,6-trinitrophenol (TNP) was successfully developed. Via the 980 nm near-infrared (NIR) irradiation, these nanosensors emit strong white UC luminescence with five typical emission peaks centered at 363, 455, 475, 546, and 654 nm. The UC emission at both 363 and 546 nm was quenched by the addition of TNT; however, the ratio of luminescence intensity at 363 nm to 546 nm (I363/I546) had no change with the increase of TNT concentration. Meanwhile, only violet UC emission at 363 nm was dramatically quenched via the addition of TNP, and the I363/I546 ratio is negatively proportional to the TNP concentration in the range of 0.01-4.5 μg/mL of TNP. On the other hand, the green UC emission intensity at 546 nm is in negative proportion to the concentration of TNT. Moreover, cyclohexane, toluene, and other nitroaromatics (such as 2,4-dinitrotoluene (DNT) and nitrobenzene (NB)) have no influence on the detection. Therefore, we developed a facile method for the simultaneous and selective detection of TNT and TNP in the mixture solution of nitroaromatics independent of complicated instruments and sample pretreatment.
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Affiliation(s)
- Yingxin Ma
- State Key Laboratory of Chemical Resource Engineering, Beijing Key Laboratory of Environmentally Harmful Chemical Analysis, Beijing University of Chemical Technology , Beijing 100029, China
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Ma Y, Huang S, Wang L. Multifunctional inorganic–organic hybrid nanospheres for rapid and selective luminescence detection of TNT in mixed nitroaromatics via magnetic separation. Talanta 2013; 116:535-40. [DOI: 10.1016/j.talanta.2013.07.033] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Revised: 07/13/2013] [Accepted: 07/16/2013] [Indexed: 10/26/2022]
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Caygill JS, Collyer SD, Holmes JL, Davis F, Higson SPJ. Electrochemical Detection of TNT at Cobalt Phthalocyanine Mediated Screen-Printed Electrodes and Application to Detection of Airborne Vapours. ELECTROANAL 2013. [DOI: 10.1002/elan.201300327] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Salgado-Figueroa P, Jara-Ulloa P, Alvarez-Lueje A, Squella JA. Sensitive Determination of Nitrofurantoin by Flow Injection Analysis Using Carbon Nanofiber Screen Printed Electrodes. ELECTROANAL 2013. [DOI: 10.1002/elan.201300065] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Fierke MA, Olson EJ, Bühlmann P, Stein A. Receptor-based detection of 2,4-dinitrotoluene using modified three-dimensionally ordered macroporous carbon electrodes. ACS APPLIED MATERIALS & INTERFACES 2012; 4:4731-4739. [PMID: 22905948 DOI: 10.1021/am301108a] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Detection of explosives, such as 2,4,6-trinitrotoluene (TNT), is becoming increasingly important. Here, 2,4-dinitrotoluene (DNT, a common analogue of TNT) is detected electrochemically. A receptor based electrode for the detection of DNT was prepared by modifying the surface of the walls of three-dimensionally ordered macroporous (3DOM) carbon. Nitrophenyl groups were first attached by the electrochemical reduction of 4-nitrobenzenediazonium ions, followed by potentiostatic reduction to aminophenyl groups. Chemical functionalization reactions were then performed to synthesize the receptor, which contains two urea groups, and a terminal primary amine. Detection of DNT using cyclic voltammetry was impeded by a large background current that resulted from the capacitance of 3DOM carbon. Detection by square wave voltammetry eliminated the background current and improved the detection limit. Unfunctionalized 3DOM carbon electrodes showed no response to DNT, whereas the receptor-modified electrodes responded to DNT with a detection limit of 10 μM. Detection of DNT was possible even in the presence of interferents such as nitrobenzene.
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Affiliation(s)
- Melissa A Fierke
- Department of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, USA
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Vuki M, Shiu KK, Galik M, O'Mahony AM, Wang J. Simultaneous electrochemical measurement of metal and organic propellant constituents of gunshot residues. Analyst 2012; 137:3265-70. [DOI: 10.1039/c2an35379b] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Galik M, O'Mahony AM, Wang J. Cyclic and Square-Wave Voltammetric Signatures of Nitro-Containing Explosives. ELECTROANAL 2011. [DOI: 10.1002/elan.201000754] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Fu XC, Chen X, Wang J, Liu JH, Huang XJ. Amino functionalized mesoporous silica microspheres with perpendicularly aligned mesopore channels for electrochemical detection of trace 2,4,6-trinitrotoluene. Electrochim Acta 2010. [DOI: 10.1016/j.electacta.2010.09.045] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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McGuire N, Honeychurch K, Hart J. The Electrochemical Behavior of Nitrazepam at a Screen-Printed Carbon Electrode and Its Determination in Beverages by Adsorptive Stripping Voltammetry. ELECTROANAL 2009. [DOI: 10.1002/elan.200904667] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Lee SR, Sawada K, Takao H, Ishida M. An enhanced glucose biosensor using charge transfer techniques. Biosens Bioelectron 2008; 24:650-6. [DOI: 10.1016/j.bios.2008.06.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2008] [Revised: 06/05/2008] [Accepted: 06/09/2008] [Indexed: 11/29/2022]
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Trammell SA, Velez F, Charles PT, Kusterbeck A. Electrochemical Detection of 2,4,6-Trinitrotoluene Using Interdigitated Array Electrodes. ANAL LETT 2008. [DOI: 10.1080/00032710802363404] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Lee SR, Lee YT, Sawada K, Takao H, Ishida M. Development of a disposable glucose biosensor using electroless-plated Au/Ni/copper low electrical resistance electrodes. Biosens Bioelectron 2008; 24:410-4. [PMID: 18524563 DOI: 10.1016/j.bios.2008.04.017] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2007] [Revised: 03/27/2008] [Accepted: 04/21/2008] [Indexed: 10/22/2022]
Abstract
This paper presents a glucose biosensor, which was developed using a Au/Ni/copper electrode. Until now, research regarding the low electrical resistance and uniformity of this biosensor electrode has not been conducted. Glucose oxidase (GOD) immobilized on the electrode effectively plays the role of an electron shuttle, and allows glucose to be detected at 0.055 V with a dramatically reduced resistance to easily oxidizable constituents. The Au/Ni/copper electrode has a low electrical resistance, which is less than 0.01 Omega, and it may be possible to mass produce the biosensor electrode with a uniform electrical resistance. The low electrical resistance has the advantage in that the redox peak occurs at a low applied potential. Using a low operating potential (0.055 V), the GOD/Au/Ni/copper structure creates a good sensitivity to detect glucose, and efficiently excludes interferences from common coexisting substances. The GOD/Au/Ni/copper sensor exhibits a relatively short response time (about 3s), and a sensitivity of 0.85 microA mM(-1) with a linear range of buffer to 33 mM of glucose. The sensor has excellent reproducibility with a correlation coefficient of 0.9989 (n=100 times) and a total non-linearity error of 3.17%.
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Affiliation(s)
- Seung-Ro Lee
- Department of Electrical and Electronic Engineering, Toyohashi University of Technology, Toyohashi, Aichi, Japan.
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Wang J, Liu G, Wu H, Lin Y. Sensitive electrochemical immunoassay for 2,4,6-trinitrotoluene based on functionalized silica nanoparticle labels. Anal Chim Acta 2008; 610:112-8. [PMID: 18267147 DOI: 10.1016/j.aca.2008.01.024] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2007] [Revised: 12/26/2007] [Accepted: 01/05/2008] [Indexed: 10/22/2022]
Abstract
We present a poly(guanine)-functionalized silica nanoparticle (NP) label-based electrochemical immunoassay for sensitively detecting 2,4,6-trinitrotoluene (TNT). This immunoassay takes advantage of magnetic bead-based platform for competitive displacement immunoreactions and separation, and use electroactive nanoparticles as labels for signal amplification. For this assay, anti-TNT-coated magnetic beads interacted with TNT analog-conjugated poly(guanine)-silica NPs and formed analog-anti-TNT immunocomplexes on magnetic beads. The immunocomplexes coated magnetic beads were exposed to TNT samples, which resulted in displacing the analog conjugated poly(guanine) silica NPs into solution by TNT. In contrast, there are no guanine residues releasing into the solution in the absence of TNT. The reaction solution was then separated from the magnetic beads and transferred to the electrode surface for electrochemical measurements of guanine oxidation with Ru(bpy)3(2+) as mediator. The sensitivity of this TNT assay was greatly enhanced through dual signal amplifications: (1) a large amount of guanine residues on silica nanoparticles are introduced into the test solution by displacement immunoreactions and (2) a Ru(bpy)3(2+)-induced guanine catalytic oxidation further enhances the electrochemical signal. Some experimental parameters for the nanoparticle label-based electrochemical immunoassay were studied and the performance of this assay was evaluated. The method is found to be very sensitive and the detection limit of this assay is approximately 0.1 ng mL(-1) TNT. The electrochemical immunoassay based on the poly[guanine]-functionalized silica NP label offers a new approach for sensitive detection of explosives.
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Affiliation(s)
- Jun Wang
- Pacific Northwest National Laboratory, Richland, WA 99352, United States
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Honeychurch K, Hart J. Voltammetric Behavior ofp-Nitrophenol and Its Trace Determination in Human Urine by Liquid Chromatography with a Dual Reductive Mode Electrochemical Detection System. ELECTROANAL 2007. [DOI: 10.1002/elan.200703989] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Hart JP, Crew A, Crouch E, Honeychurch KC, Pemberton RM. Some Recent Designs and Developments of Screen‐Printed Carbon Electrochemical Sensors/Biosensors for Biomedical, Environmental, and Industrial Analyses. ANAL LETT 2007. [DOI: 10.1081/al-120030682] [Citation(s) in RCA: 182] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Hart JP, Crew A, Crouch E, Honeychurch KC, Pemberton RM. Chapter 23 Screen-printed electrochemical (bio)sensors in biomedical, environmental and industrial applications. ELECTROCHEMICAL SENSOR ANALYSIS 2007. [DOI: 10.1016/s0166-526x(06)49023-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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Chen JC, Shih JL, Liu CH, Kuo MY, Zen JM. Disposable Electrochemical Sensor for Determination of Nitroaromatic Compounds by a Single-Run Approach. Anal Chem 2006; 78:3752-7. [PMID: 16737233 DOI: 10.1021/ac060002n] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Environmental and security applications have generated major demands for effective field-deployable tools for detecting nitroaromatic compounds, such as chloramphenicol (an antibiotic), parathion (an organophosphate nerve agent), and TNT (2,4,6-trinitrotoluene, an explosive) in a fast, simple, sensitive, reliable, and cost-effective manner. We report here a single-run approach for such a purpose. The reduction potential of different nitroaromatic compounds was found to systematically shift with the substituent group at an electrochemically preanodized screen-printed carbon electrode. The preanodization treatment makes the peak sharp and hence provides a precise way to identify the substituent effect on nitroaromatic compounds. By using potential shifts as analytical characteristics of nitroaromatic compounds, a suitable internal standard can be chosen based on the criteria of well-separated peak potential and rarely found in the real sample of interest. Simply by measuring the ratio of peak currents between analytes of interest and internal standard, the analysis can be done in a single-run measurement. Both the matrix effect and the variation of electrode during the preparation process can be canceled out in this approach and thus allows for a high-precision analysis. Just by placing a 20-microL drop on a single-use amperometric sensor strip incorporating a three-electrode configuration is enough for rapid and sensitive detection of nitroaromatic compounds by square-wave voltammetry. For example, the linear detection range can be up to 100 microM with a detection limit of 0.42 microM (S/N = 3) in the detection of chloramphenicol. This approach was successfully demonstrated in real sample analysis to verify the applicability of the method. The promising performances open new possibilities for rapid determination of nitroaromatic compounds in environmental and biological samples.
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Affiliation(s)
- Jyh-Cheng Chen
- Department of Chemistry, National Chung Hsing University, Taichung 402, Taiwan
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Honeychurch KC, Smith GC, Hart JP. Voltammetric Behavior of Nitrazepam and Its Determination in Serum Using Liquid Chromatography with Redox Mode Dual-Electrode Detection. Anal Chem 2005; 78:416-23. [PMID: 16408922 DOI: 10.1021/ac058035a] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A method involving high-performance liquid chromatography with dual-electrode electrochemical detection in the redox mode (LC-DED) has been successfully developed for the determination of the benzodiazepine tranquilizer, nitrazepam, in serum. To elucidate the electrochemical mechanism occurring at a glassy carbon electrode, cyclic voltammetry was preformed with 1 mM solutions of nitrazepam at pH values between 2 and 12, using a potential range from -1.5 to +1.5 V. Two reduction peaks were observed over the whole pH range; the first, designated R1, was consistent with the 4e-, 4H+ reduction of the 7-nitro group to a hydroxylamine species; the second more negative peak, designated R2, was shown to be the result of a 2e-, 2H+ reduction of the 4-5 azomethine group. On the reverse anodic scan, an oxidation signal was observed, designated O1, which was considered to result from a 2e-, 2H+ oxidation of the hydroxylamine to a nitroso group. On the second forward scan, a new reduction peak, designated R3, was observed, which was considered to result from reduction of the nitroso species back to the hydroxylamine species. Studies were then undertaken to exploit the hydroxylamine/nitroso redox couple using LC-DED detection for the measurement of nitrazepam in serum. The optimal chromatographic conditions were found to comprise a mobile phase containing 60% methanol, 40% 50 mM pH 4.1 acetate buffer, in conjunction with a Hypersil C18 250 mm x 4.6 mm column. Hydrodynamic voltammetric studies were undertaken to optimize the operating potentials required for dual-electrode detection. It was found that an applied potential of -2.4 V was optimum for the "generator" cell and +0.5 V for the "detector" cell. The proposed method was evaluated by carrying out replicate nitrazepam determinations on spiked bovine and human serum samples. The former evaluation was preformed at a concentration of 11.2 microg mL(-1), and the latter at 1670 ng mL(-1). For bovine serum, the recovery of nitrazepam was found to be 75.8% and the associated coefficient of variation was 6.1% (n = 6). For human serum, the recovery was 74.1% with a coefficient of variation of 7.8% (n = 7). These data suggest that the method holds promise for applications in toxicology and where an alternative reliable method to confirm drug abuse may be required.
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Affiliation(s)
- Kevin C Honeychurch
- Centre for Research in Analytical, Materials and Sensors Science, Faculty of Applied Sciences, University of the West of England, Bristol, Frenchay Campus, Coldharbour Lane, Bristol, BS16 1QY, UK
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Agüí L, Vega-Montenegro D, Yáñez-Sedeño P, Pingarrón JM. Rapid voltammetric determination of nitroaromatic explosives at electrochemically activated carbon-fibre electrodes. Anal Bioanal Chem 2005; 382:381-7. [PMID: 15830191 DOI: 10.1007/s00216-004-3017-z] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2004] [Revised: 11/26/2004] [Accepted: 12/01/2004] [Indexed: 10/25/2022]
Abstract
The electrochemical behaviour of some nitroaromatic explosives (2,4,6-trinitrotoluene, TNT; 2,6-dinitrotoluene, 2,6-DNT; 2-nitrotoluene, 2-NT; 2-amino-4,6-dinitrotoluene, 2-A-4,6-DNT; 3,5-dinitroaniline, 3,5-DNA; and nitrobenzene, NB) at electrochemically activated carbon-fibre microelectrodes is reported. Electrochemical activation of such electrode material by repeated square-wave (SW) voltammetric scans between 0.0 and +2.6 V versus Ag/AgCl, produced a dramatic increase in the cathodic response from these compounds. This is attributed to the increase of the carbon-fibre surface area, because of its fracture, and the appearance of deep fissures along the main fibre axis into which the nitroaromatic compounds penetrate. Based on the important contribution of adsorption and/or thin layer electrolysis to the total voltammetric response, a SW voltammetric method for rapid detection of nitroaromatic explosives was developed. No interference was found from compounds such as hydrazine, phenolic compounds, carbamates, triazines or surfactants. The limits of detection obtained are approximately 0.03 microg mL(-1) for all the nitroaromatic compounds tested. The method was applied for the determination of TNT in water and soil spiked samples; recoveries were higher than 95% in all cases.
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Affiliation(s)
- Lourdes Agüí
- Department of Analytical Chemistry, Faculty of Chemistry, University Complutense of Madrid, 28040, Madrid, Spain
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