Site-regulated CoNFs-NH2@PtNPs nanozyme-based all-in-one portable detection of organophosphorus pesticides integrating deep learning and hardware logic gates.

Abstract

Widespread use of organophosphorus pesticides (OPs) has led to pervasive environmental residues and potential human health hazards, making rapid, sensitive, and portable on-site OPs detection urgently needed. In this work, an amino-functionalized cobalt nanoflower-supported platinum nanoparticle composite (CoNFs-NH2@PtNPs) was successfully fabricated. Combined with steady-state kinetic experiments and density functional theory calculations, the modulation mechanism of amino modification on the electron-donating ability of Pt active sites and oxygen activation performance was systematically clarified. Taking advantage of the inherent oxidase-like activity and fluorescence properties of CoNFs-NH2@PtNPs, a colorimetric-fluorescent dual-mode sensor was constructed based on acetylcholinesterase inhibition for high-efficiency OPs detection. Furthermore, a low-cost integrated portable detection platform was developed by integrating 3D-printed dark-box hardware, MCU control modules, smartphone imaging technology, and self-built sensing algorithms. This platform realizes intuitive qualitative grading via LED indicator lights based on solution RGB signal changes and intelligent quantitative detection through a customized smartphone mini-program. The established all-in-one detection system effectively addresses the poor portability and inferior real-time performance of traditional OPs detection methods, providing a reliable and practical strategy for field pesticide residue monitoring.