Acetylcholinesterase electrochemical biosensors with graphene-Au nanoparticles-Ti3C2Tx modified for detection of organophosphate pesticides

An acetylcholinesterase biosensor was prepared with graphene-Au nanoparticle-transition metal carbide modified for the detection of organophosphorus pesticides. The outstanding electrical properties, specific surface area and biocompatibility of graphene and excessive metal carbide, especially under the modification of gold nanoparticles, make the biosensor highly sensitive. Cyclic voltammetry and differential pulse voltammetry were used to characterize the electrochemical catalysis of the biosensor: acetylcholinesterase/chitosan-transition metal carbides/gold nanoparticle/graphene/glassy carbon electrode. The prepared biosensor has a good linear relationship with dichlorvos, a common organophosphorus pesticide, from 2.26 × 10−3 to 2.26 × 10−8 mM and the limit of detection was 1.25 × 10−8 mM. Finally, the biosensor exhibits good stability, can be stored at room temperature for one month without significant performance degradation.