The invention discloses an
enzyme biosensor for
rapid detection of organophosphorus
pesticide dimethoate as well as preparation and application of the
enzyme biosensor, and relates to the field of electrochemical sensors. The method comprises the following steps: preparing GR / GCE, preparing AuNPs / GR / GCE, and preparing AChE / AuNPs / GR / GCE.
Graphene and gold nanoparticles are compounded to form AuNPs / GR / GCE, the electrochemical impedance of the
glassy carbon electrode is remarkably reduced, the effective specific surface area of the
glassy carbon electrode is increased, the
electron transfer rate of the surface of the
glassy carbon electrode is increased, rich binding sites are provided for immobilization of
enzyme molecules, the stability of enzyme is improved, and degradation or inactivation of the enzyme in the using process is reduced;
acetylcholine esterase is used as a recognition probe, AChE / AuNPs / GR / GCE is constructed on AuNPs / GR / GCE in a self-
assembly mode,
dimethoate can prevent acetyl thiocholine
iodide from being hydrolyzed to generate thiocholine,
electrochemical response signals are reduced, and the
dimethoate has good
electrochemical response signals, so that the organophosphorus
pesticide dimethoate residue is rapidly, accurately and safely screened on site.