University of North Florida
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Contact Info

Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Email: schalk@unf.edu
Website: @unf

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Robert Wilson

Abbrev:
Wilson, R.
Other Names:
Address:
Department of Chemistry, Liverpool University, Liverpool L69 7ZD, England
Phone:
[44] (151) 794 3573
Fax:
[44] (151) 794 3588

Citations 6

"Paramagnetic Bead Based Enzyme Electrochemiluminescence Immunoassay For TNT"
J. Electroanal. Chem. 2003 Volume 557, Issue 1 Pages 109-118
Robert Wilson, Charles Clavering and Alistair Hutchinson

Abstract: We have developed an electrochemiluminescence immunoassay system for TNT (2,4,6-trinitrotoluene) in which enzyme labelled antibodies bound to paramagnetic beads are concentrated on an electrode magnetically, and light emission is triggered electrochemically. Full details of the instrumentation used to carry out these immunoassays are described. The paramagnetic beads are coated with haptenylated dextrans prepared by substituting biotin and analogues of TNT into aminodextrans. Three methods for synthesizing aminodextrans are compared and a method for substituting haptens and biotin into aminodextrans is described. Antibodies to TNT were labelled with glucose oxidase, and used for immunoassays in which TNT and haptenylated dextran competed for a limited number of antibody binding sites. The haptenylated dextran was bound to streptavidin coated paramagnetic beads, and the antibodies bound to the dextran were separated from the sample by concentrating them on an electrode magnetically. Bound antibodies were quantified by integrating the light emitted when enzymatically generated H2O2 reacted with electrochemically-oxidized luminol. The time taken for the detection step was 80 s compared with 20 min for colorimetric ELISAs using the same reagents, and the limit of detection for TNT was 31 ppb (3 x S.D. zero calibrator; n=8).

"Electrochemiluminescence Of 2 ,6 -difluorophenyl 10-methyl-9,10-dihydroacridine-9-carboxylate"
Chem. Commun. 2000 Volume 2000, Issue 20 Pages 2067-2068
Robert Wilson, Hashem Akhavan-Tafti, Renuka DeSilva, A. Paul Schaap

Abstract: Electrochemical oxidation of the acridine ester 2,6-difluorophenyl-10-methyl-9,10-dihydroacridine-9-carboxylate yields the corresponding acridinium ester which reacts with H2O2 to generate intense chemiluminescence.

"Electrochemiluminescence Flow Injection Immunoassay For Atrazine"
Biosens. Bioelectron. 1997 Volume 12, Issue 4 Pages 277-286
Robert Wilson*, Michael H. Barker, David J. Schiffrin and Ram Abuknesha

Abstract: Antibodies to atrazine were labelled with glucose oxidase and used in colorimetric enzyme linked immunosorbent assays. Transparent aminosilanized indium tin oxide coated glass electrodes were derivatized with aminodextran covalently modified with atrazine caproic acid. The labelled antibodies were used to investigate the derivatized electrodes colorimetrically and the electrodes were use in an electrochemiluminescence flow injection analyzer.. Electrochemiluminescence immunoassay for atrazine in the range 0-10 ppb showed that it was possible to detect less than 0.1 ppb, the precautionary limit for pesticides in drinking water recommended by the European Commission.
Atrazine Pesticides Water Chemiluminescence Immunoassay Electrode Electrode Apparatus Detector

"Electrochemiluminescence Detection Of Glucose Oxidase As A Model For Flow Injection Immunoassays"
Biosens. Bioelectron. 1996 Volume 11, Issue 8 Pages 805-810
Robert Wilson*, Jens Kremeskötter, David J. Schiffrin and James S. Wilkinson

Abstract: Electrochemical microassays based on the reaction between enzymatically generated H2O2 and electrochemically oxidized luminol were studied using immobilized glucose oxidase (GOD) as the model enzyme and glucose as substrate. GOD was covalently immobilized on to aminosilanized indium tin oxide-coated glass wafers which served as the working electrode (stainless-steel counter electrode) in the flow-through detection cell. The assays were performed by injecting 110 µL 10 mM KCl/glucose/100 µM-luminol of pH 9 into the carrier stream (0.475 ml/min) of 10 mM KCl of pH 9. The generated light was detected by a photomultiplier tube (operating potential not given). The calibration graph was linear up to 10 mM glucose and the detection limit was 0.419 mM. The presence of paracetamol, vitamin C and uric acid suppressed the chemiluminescence.
Glucose Chemiluminescence Immunoassay

"Electrochemiluminescence Determination Of 2 ,6 -difluorophenyl 10-methylacridan-9-carboxylate"
Anal. Chem. 2001 Volume 73, Issue 4 Pages 763-767
Robert Wilson, Hashem Akhavan-Tafti, Renuka DeSilva, and A. Paul Schaap

Abstract: Electrochemical oxidation of the acridan 2,6-difluorophenyl-10-methylacridan-9-carboxylate produces the corresponding acridinium ester, which reacts with hydrogen peroxide forming a dioxetanone intermediate. Decomposition of the dioxetanone generates light at 430 nm when it relaxes to the ground state. The effect of pH and hydrogen peroxide concentration on this ECL reaction and on the stability of the acridan were investigated. At pH 8.0 and a hydrogen peroxide concentration of 10 mM, light emission from the ECL reaction was used to determine the acridan concentration with a detection limit of 54 pmol L-1. Results suggest that acridan esters could be used as labels in ECL immunoassays and nucleotide assays.

"Electrochemiluminescence Enzyme Immunoassay For TNT"
Analyst 2003 Volume 128, Issue 5 Pages 480-485
Robert Wilson, Charles Clavering and Alistair Hutchinson

Abstract: Details of an electrochemiluminescence (ECL) enzyme immunoassay for TNT (2,4,6-trinitrotoluene) are reported. The design and construction of a computer controlled flow injection electrochemiluminometer in which the immunoassays are carried out is described. This system is used to select and pump solutions through a flow cell, which contains a gold working electrode as part of a three-electrode arrangement. The deposition of a re-usable immunosorbent dextran surface anchored to a gold surface in the flow cell by chemiadsorbed thiol groups is described. Antibodies are labeled with the enzyme glucose oxidase and used in competitive immunoassays in which the separation step is carried out by concentrating unbound antibodies on the immunosorbent surface. Hydrogen peroxide generated by the enzyme label when glucose is pumped through the flow cell is detected using luminol ECL. Light intensity was inversely proportional to the concentration of TNT in the sample in the range 0-100 ppb. The results are compared with colorimetric ELISA's carried out using the same reagents, and potential for developing a portable instrument for use in the field is discussed.