Selective Determination of Mefformin in Urine Sample based on Molecularly Imprinted Polymer-Chemiluminescence Sensor

A flow-injection chemiluminescence (FT-CL) sensor for metformin determination based on recognition materials of molecularly imprinted polymers (MIP) is reported. The sensor was fabricated by packing the MIP particles into a V-shape flow cell. Metformin could be selectively on-line adsorbed by the MIPs and then sensed by its great enhancing effect on the weak CL reaction between N-bromosuccinimide (NBS) and fluorescein. The CL intensity was linear to metformin concentration in the range from 2x10(-8) to 8x10(-6) g.mL(-1) and the limit of detection (L.O.D.) was 6x10(-9) g-mL(-1) (3 sigma). The sensor showed high selectivity, improved sensitivity and excellent stability and reversibility compared with the CL method without using MIPs. The lifetime of the sensor was investigated and MIPs could be reused for more than 200 times. The sensor has been directly applied to determine metformin in human urine.