Rational Integration of Biomineralization, Microbial Surface Display, and Carbon Nanocomposites: Ultrasensitive and Selective Biosensor for Traces of Pesticides

Abstract Nowadays, the over misuse of organophosphate pesticides (OPP) has seriously threatened human health and environment, and it is challenging and indispensable to establish biosensor for supersensitive, reliable, and fast detection of traces of OPP in real samples. This work provides an interdisciplinary strategy for the construction of electrochemical OPP biosensor with supersensitivity, high selectivity, simple operation, and fast response. First, amino acid ionic liquid (AAIL) is used as stabilizer to dramatically improve the dispersibility of carbon nanotube (CNT) in the water phase, so that the obtained CNT@AAIL composites show good conductivity, biocompatibility, and electrocatalytic activity. Further, CNT@AAIL composites are employed to improve the conductivity and electrochemical activity of mineralized organophosphate hydrolase (OPH)‐fused cell (M‐Cell) with excellent catalytic activity for the fabrication of electrochemical biosensor. Based on synergistic effects of CNT@AAIL and M‐Cell, the constructed biosensor shows 2–8 orders of magnitude lower limit of detection (3 fmol L⁻¹) than those of reported OPP analytic methods. In addition, due to the specificity of OPH and detection at negative potential, the biosensor shows excellent selectivity. In addition, the biosensor also demonstrates the acceptable reliability for the traces of pesticides in real samples. This work will open an interdisciplinary avenue for supersensitive electrochemical biosensor.