Acetylcholinesterase electrochemical biosensors with graphene-transition metal carbides nanocomposites modified for detection of organophosphate pesticides

• Published in: PloS one 2020-04, Vol.15 (4), p.e0231981
• Main Authors: Wang, Bo, Li, Yiru, Hu, Huaying, Shu, Wenhao, Yang, Lianqiao, Zhang, Jianhua
• Format: Article
• Language: English
• Subjects: Acetylcholine; Acetylcholinesterase; Acetylcholinesterase - metabolism; Biocompatibility; Biology and Life Sciences; Biosensing Techniques - methods; Biosensors; Carbides; Catalysis; Chitosan; Detection equipment; Dichlorvos; Education; Electric properties; Electrical properties; Electrochemical impedance spectroscopy; Electrochemical Techniques; Electrochemistry; Electrodes; Engineering and Technology; Enzymes; Enzymes, Immobilized - chemistry; Enzymes, Immobilized - metabolism; Glassy carbon; Graphene; Graphite; Graphite - chemistry; Laboratories; Limit of Detection; Medical equipment; Metal carbides; Metals; Metals (Materials); Methods; Morphology; Nanocomposites; Nanocomposites - chemistry; Nanomaterials; Optimization; Organophosphates; Organophosphorus Compounds - analysis; Organophosphorus pesticides; Performance degradation; Pesticides; Pesticides - analysis; Physical Sciences; Reproducibility of Results; Research and Analysis Methods; Room temperature; Sensors; Spectroscopy; Titanium - chemistry; Transition Elements - chemistry; Transition metal compounds; Transition metals; Voltammetry; Work stations
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0231981

An acetylcholinesterase biosensor modified with graphene and transition metal carbides was prepared to detect organophosphorus pesticides. Cyclic voltammetry, differential pulse voltammetry, and electrochemical impedance spectroscopy were used to characterize the electrochemical catalysis of the biosensor: acetylcholinesterase/chitosan-transition metal carbides/graphene/glassy carbon electrode. With the joint modification of graphene and transition metal carbides, the biosensor has a good performance in detecting dichlorvos with a linear relationship from 11.31 μM to 22.6 nM and the limit of detection was 14.45 nM. Under the premise of parameter optimization, the biosensor showed a good catalytic performance for acetylcholine. Compared to the biosensors without modification, it expressed a better catalytic performance due to the excellent electrical properties, biocompatibility and high specific surface area of graphene, transition metal carbides. Finally, the biosensor exhibits good stability, which can be stored at room temperature for one month without significant performance degradation, and has practical potential for sample testing.