Title: Carbon quantum dots and Acetylcholinesterase- based fluorescent biosensor for pesticide detection in waters

Biography:

Maria Isabel Gaviria Arroyave, currently Ph.D. (c) in Environmental Engineering at Universidad de Antioquia and CEO of Taxia mentoring start-up. Degree in Biological Engineering from Universidad nacional de Colombia and Master in Engineering from Universidad de Antioquia. Up to 10 years of experience in innovation and development processes, applying cutting-edge technologies like environmental biotechnology and green nanotechnology. Previous positions in R&D manager at Universidad EIA and Biotechnology chief in SENA. Senior consultant in innovation and circular economy for Taxia mentoring and Distilled innovation. National doctoral fellowship from Minciencias (2018-present) and Swiss government fellowship from University of St.Gallen (AIT program 2020-2021).

Abstract

Water sources in rural areas are exposed to harmful Organophosphorus pesticides (OP) that should be detected before human consumption [1], and biosensors have emerged as an alternative [2]. The application of nanomaterials, including carbon quantum dots (CD), can significantly improve the performance of optical biosensors. In this work, naturally fluorescent and non-toxic CD synthesized previously [3]from African-oil palm biochar were integrated with Acetylcholinesterase enzyme (AChE) as a bioreceptor, to produce a fluorescent biosensor. This system is modulated with graphene oxide (OG), showing a fluorescence recovery in the presence of the OP. The biosensor was evaluated under pure chlorpyrifos, but also under a commercial formulation called Lorsban®. We obtained a limit of detection (LOD) as low as 0.13 ppb and 2.14 ppb for chlorpyrifos and Lorsban® respectively. The system also shows a good selectivity against proteins and other organic substances usually present in drinking water, even in tests with tap water.