Versatile biomimetic catalyst functionalized nanozymes for electrochemical sensing

Electrochemical sensors face challenges in the readily accessible versatile sensing materials, robust signal transmission and selective detection of analytes in complex systems. Herein, we report a simple one-pot approach using commercially available materials to synthesize versatile biomimetic catalyst functionalized nanozymes for multifunctional electrochemical sensors. Nanoenzymes were synthesized by in situ polymerization of 3,4-ethylenedioxythiophene (EDOT) on graphene (GR) while integrating biomimetic catalysts into nanosheets. The resulting nanozymes exhibited stable and efficient catalysis activity and interfacial signal transmission through electrostatic and π-π interactions, as well as charge transfer at the active centers. By virtue of excellent electron transfer and favorable cascade catalysis effect, the biosensor based on sulfonated cobalt phthalocyanine functionalized nanozymes (CoPcNS) and acetylcholinesterase (AChE) exhibited superior catalytic activity and robust stability. This one-pot method was also used to prepare nanozymes with diverse biomimetic catalysts (metallophthalocyanine and metalloporphyrin), achieving specific detection of various biomolecules (H2O2, NO, etc.). A portable biosensing device based on a screen-printed electrode was developed, featuring a low limit of detection, ultralow working potential, high anti-interference capability, and good applicability for the rapid detection of organophosphorus pesticides (OPs) in real samples. Our research presents a promising guide for the rational fabrication of versatile biomimetic catalyst-functionalized nanozymes, advancing the development of electrochemical sensors in environmental and biological fields.