Mediated self-assembled gold nanoclusters with mesoporous silica particles to boost fluorescence for enhanced on-site monitoring of organophosphate pesticides

Accurate detection of organophosphate pesticides (OPs) is paramount for ensuring food safety. Dendritic mesoporous silica sphere was employed to confine gold nanoclusters (AuNCs@dmSiO 2 ) to ameliorate fluorescent property of AuNCs. A AuNCs@dmSiO 2 -based fluorescent method was developed for OPs sensing. Identification of Cu 2+ by AuNCs quenched AuNCs@dmSiO 2 fluorescence. Interaction between Cu 2+ and generated thiocholine in catalysis of acetylcholinesterase (AChE) caused fluorescence enhancement. OPs, an inhibitor of AChE, suppressed thiocholine production to cause fluorescence quenching. Based on fluorescent variation, a fluorescent method was proposed for OPs by selecting paraoxon as a model within range of 0.05–25.0 ng/mL with a limit of detection (LOD) of 0.032 ng/mL. Besides, a portable test swab was prepared for on-site monitoring OP paraoxon with a smartphone-based 3D-printing portable device with a LOD of 0.65 ng/mL. This work is highlighted by the inspiration of designing highly fluorescent AuNCs, and the provision of a viable avenue for OPs-related food analysis.