Nanosized Difunctional Photo Responsive Magnetic Imprinting Polymer for Electrochemically Monitored Light-Driven...

Herein, a novel photoresponsive magnetic electrochemical imprinting sensor for the selective extraction of paracetamol from biological samples was designed. In particular, nanosized photoresponsive molecular imprinted polymers were prepared on the surface of magnetic Fe₃O₄ nanoparticles through living radical polymerization of azobenzene. The introduction of a magnetic-controlled glassy carbon electrode makes the immobilization and removal of nanosized photoresponsive molecular imprinted polymers on the magnetic-controlled glassy carbon electrode surface facilely operational. With the photoresponsive property, the sensor undergoes reversible release and uptake of paracetamol upon alternative irradiation at 365 and 440 nm basing on a configurational change of azobenzene monomer in the photoresponsive molecular imprinted polymers receptor sites. Simultaneously, these processes are monitored by the photoresponsive changes of electrochemical signal from paracetamol. Two linear ranges from 0.001 to 0.7 mmol L^-1 (R² = 0.96) and 0.7 to 7 mmol L^-1 (R² = 0.95) for paracetamol determination were obtained with a quantification limit of 0.000 86 mmol L^-1 and a detection limit of 0.000 43 mmol L^-1. The recoveries of paracetamol in the urine as determined by photoresponsive molecular imprinted polymers extraction were varied between 87.5% and 93.3%. As a consequence, combining photocontrolled selective extraction, interfacial stability from magnetic adsorption, and specifically electrochemical response, the photoresponsive molecular imprinted polymers sensor shows significant advantages for simultaneous separation, enrichment, and detection of trace paracetamol in biological samples.