SELECTIVE DETERMINATION OF PARAOXON (NEUROTOXIN) USING ESTERASE-2 MUTANT-BASED NANOSTRUCTURED AMPEROMETRIC BIOSENSORS.

Autor: Magar HS; Applied Organic Chemistry Department, National Research Centre (NRC), Dokki, Giza 12622, Egypt., Fayez M; Biosensors Research Lab, Zewail City of Science and Technology, 6th October City, Giza 12578, Egypt., Febbraio F; Institute of Biochemistry and Cell Biology, National Research Council (CNR), Via P. Castellino 111, 80131 Naples. Electronic address: ferdinando.febbraio@cnr.it., Hassan RYA; Biosensors Research Lab, Zewail City of Science and Technology, 6th October City, Giza 12578, Egypt; Applied Organic Chemistry Department, National Research Centre (NRC), Dokki, Giza 12622, Egypt. Electronic address: ryounes@zewailcity.edu.eg.
Jazyk: angličtina
Zdroj: Analytical biochemistry [Anal Biochem] 2024 Dec 14, pp. 115751. Date of Electronic Publication: 2024 Dec 14.
DOI: 10.1016/j.ab.2024.115751
Abstrakt: Organophosphate pesticides (OPs) are causing non-selective inhibition in enzymatic bioreceptors, thus the enzymatic-inhibition-based traditional assays are not suitable for their specific detection in food and environmental samples. Accordingly, a selective nanostructured electrochemical biosensing system was designed using six mutants of the esterase-2 (EST2 protein) enzymes from A. acidocaldarius to be exploited as targeting bio-receptors for the specific detection of OPs. Each of the EST2 mutant enzymes was immobilized on disposable screen-printed electrodes modified with Aluminum oxide (Al 2 O 3 )/Copper (Cu) nanocomposite. Consequently, chronoamperometric assay was fully optimized, and cross-reactivity study was carried out using paraoxon, malathion and chlorpyrifos. The comparative cross-reactivity study was performed on the six mutant proteins in terms of inhibitory percentage over a wide range of pesticide concentrations. Eventually, a wide dynamic inhibition range was achieved while the limit of detection for the paraoxon toxicity was 0.01 nM and the limit of quantification was 0.05 nM. Finally, paraoxon was selectively determined using the newly developed EST-based biosensor in different spiked food samples.
Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this article.
(Copyright © 2024. Published by Elsevier Inc.)
Databáze: MEDLINE