RAPID ANALYSIS SYSTEM FOR TRANSACTION OF CADMIUM IN URINE BASED ON PAPER SENSORS CARRYING ZnO QUANTUM DOTS

Abstract

The invention proposes a rapid analysis system for trace amounts of cadmium in urine samples based on a paper sensor incorporating luminescent nanomaterials and mobile device image processing, including: a sample processing module using deep condensation solvent (DES) for extraction, enrichment, and removal of interfering components in urine; a dark box-type imaging chamber incorporating a stable UV excitation source and reference standard for normalizing optical signal intensity; a paper sensor with a microfluidic structure with hydrophobic regions defining the channel and reaction region; a sensing region impregnated with surface-modified ZnO quantum dots using organic ligands to increase stability and selectivity for heavy metal ions; and a mobile device with a high-sensitivity CMOS camera configured to acquire sensor images under controlled conditions.and one or more processors configured to perform image preprocessing (white balance, gamma correction, light normalization), sensor region segmentation, color feature extraction in color spaces such as RGB, build quantitative models based on the correlation between fluorescence intensity and metal ion concentration; and integrate optimization algorithms including Bayesian Optimization to update analysis conditions in a closed loop.