Upconversion-based Hydrogel Kit with Python-assisted Analysis Platform for Sample-to-result Detection of Organophosphorus Pesticide

On -site quantitative analysis of pesticide residues is crucial for monitoring environmental quality and ensuring food safety. Herein, we have developed a reliable hydrogel portable kit using NaYbF 4 @NaYF 4 : Yb, Tm upconversion nanoparticles (UCNPs) combined with MnO 2 nanoflakes. This portable kit is integrated with a smartphone reader and Python -assisted analysis platform to enable sample -to -result analysis for chlorpyrifos. The novel UCNPs maximizes energy donation to MnO 2 acceptor by employing 100 % of activator Yb 3 + in the nucleus for NIR excitation energy collection and confining emitter Tm 3 + to the surface layer to shorten energy transfer distance. Under NIR excitation, efficient quenching of upconversion blue -violet emission by MnO 2 nanoflakes occurs, and the quenched emission is recovered with acetylcholinesterase-mediated reactions. This process allows for the determination of chlorpyrifos by inhibiting enzymatic activity. The UCNPs/MnO 2 were embedded to fabricate a hydrogel portable kit, the blue -violet emission images captured by smartphone were converted into corresponding gray values by Python -assisted superiority chart algorithm which achieves a real-time rapid quantitative analysis of chlorpyrifos with a detection limit of 0.17 ng mL -1 . At the same time, pseudo -color images were also added by Python in "one run" to distinguish images clearly. This sensor detection with Python -assisted analysis platform provides a new perspective on pesticide monitoring and broadens the application prospects in bioanalysis.