A fluorescent paper-based ion imprinting analytical platform for detection cadmium ions via the synergy of biomimetic recognition and AIE effect

Rapid and accurate detection of trace cadmium ions (Cd 2+ ) in the environment and foodstuff is great of significance. Herein, we developed a fluorescent paper-based analytical platform for Cd 2+ detection with dual recognition modes based on the paper-based ion imprinting chip (Cd-IIP) and an aggregation-induced emission (AIE) probe (PBQ) for the first time. Cd-IIP was prepared based on sol–gel technique using 3-mercaptopropyltriethoxysilane (MPTES) as the functional monomer, Cd 2+ as the ionic template, and tetraethyl silicate (TEOS) as the cross-linking agent. Cd-IIP could selectively enrich Cd 2+ with good adsorption capacity (385.00 mg g −1 ) and imprinting factor (IF = 5.3). Benefiting from the PBQ with specific recognition of Cd 2+ based on metal coordination-induced AIE effect, the platform exhibited superior selectivity and recognition efficiency to Cd 2+ . The platform showed a wide linear range from 0.01 to 10 μg mL −1 with the limit of detection (LOD) as low as 0.0045 μg mL −1 under the synergy of the biomimetic recognition and AIE effect. Moreover, the smartphone-based analytical method was utilized for visual detection of Cd 2+ with the LOD of 0.11 μg mL −1 in real samples. Overall, this analytical platform possessed significant specificity and sensitivity, holding a great promise of dual selective principles for efficient analysis of Cd 2+ in complex systems.