Michael Thompson

Title : Electrochemical point-of-care sensor for early diagnosis of Ovarian Cancer

Abstract:

Ovarian cancer (OC), the most lethal gynecological cancer, globally causes 150,000 deaths, annually. Notably, the 5-year survival rate is generally accepted to be over 90% if the disease is detected at Stage 1. The well-known currentCA-125diagnostictestforOChasbeenshowntoyieldbothfalsepositiveandnegativeresults,andisnotnormally employed to detect the disease at an early Stage. Accordingly, there is a prescient requirement for the introduction of a low-cost screening testthatis rapid, sensitive and selective, and that can be applied on a large-scale basis.In this regard, we have developed a simple, precise, and low-cost screening test using an electrochemical technique to fabricate a point-of-care testing (POCT) device for early detection of OC. The device detects lysophosphatidic acid (LPA), a highly promising biomarker, which has been observed to be elevated in 90% of stage I OC patients, and gradually increases as the disease progresses to later stages. This is achieved via a recognition probe, gelsolin, immobilized on medicalgrade stainless-steel electrodes. The detection technology is based on electrochemical impedance spectroscopy (EIS), whereby three-electrode setup is employed which consists of a working electrode, counter electrode, and reference electrode. The working electrode is modified to provide the recognition surface. The main challenge in developing such a tool is overcoming the ubiquitous, problematic phenomenon known as non-specific adsorption (NSA), which is due to the fouling of non-target molecules in target biological fluid on the recognition surface of the device. To overcome NSA, we have used a proprietary strategy using silane-based interfacial chemistry to modify the stainlesssteel electrodes. Research on the technology to date has demonstrated that LPA can be detected in serum at the micromolar level. In collaboration with Princess Margaret Hospital, Toronto tests on patient samples are planned.

Biography:

Professor Michael Thompson obtained his undergraduate degree from the University of Wales, UK and his PhD in analytical chemistry from McMaster University. Following a period as Science Research Council PDF at Swansea University he was appointed Lecturer in Instrumental Analysis at Loughborough University. He then moved to the University of Toronto where he is now Professor of Bioanalytical Chemistry. He has held a number of distinguished research posts including the Leverhulme Fellowship at the University of Durham and the Science Foundation Ireland E.T.S Walton Research Fellowship at the Tyndall National Institute, Cork City. He is recognized internationally for his pioneering work over many years in the area of research into new biosensor technologies and the surface chemistry of biochemical and biological entities. He has made major contributions to the label-free detection of immunochemical and nucleic acid interactions and surface behavior of cells using ultra high frequency acoustic wave physics. Recently,scanning Kelvin nanoprobe detection has been introduced which offers the multiplexed detection of biochemical phenomena. Thompson has served on the Editorial Boards of a number of major international journals including Analytical Chemistry, The Analyst, Talanta, Analytica Chimica Acta and Biosensors and Bioelectronics. He is currently Editor-in-Chief of the monograph series “Detection Science” for the Royal Society of Chemistry,UK.He has been awarded many prestigious international prizes for his research including The Robert Boyle Gold Medal of the Royal Society of Chemistry, E.W.R. Steacie Award of the Chemical Society of Canada, the Theophilus Redwood Award of the Royal Society of Chemistry and the Fisher Scientific Award in Analytical Chemistry of the Chemical Society of Canada.He was made a Fellow of the Royal Society of Canada in 1999.