Molecularly Imprinted Polymer-Chemiluminescence Sensor Detect Phentolamine in Urine Sample

Abstract

Using methacrylic acid (MAA) as monomer, ethylene glycol dimethacrylate (EGDMA) as cross-linker and phentolamine as template molecule, we synthesized phentolamine–molecularly imprinted polymers (MIP). Using phentolamine–MIP as molecule recognizates, based on the oxidation reaction between KMnO4 and phenolamine in acidic, we set up a flow-injection chemiluminescence (FI-CL) sensor for phentolamine determination. The sensor was fabricated by packing the MIP particles into a V-shape flow cell. Phentolamine could be selectively on-line adsorbed by the MIPs and then sensed by the oxidation reaction between KMnO4 and phenolamine in acidic.The CL intensity was linear to phentolamine concentration in the range from 2.0 ×10−8 to 6.0 ×10−6 g mL−1 and the limit of detection (L.O.D.) was 6.0 ×10−9 g mL−1 (3σ) with the relative standard deviation (R.S.D.) less than 5% (n=11). 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. Using the method to determine phentolamine in human urine, the recoveries of phentolamine is 100.0% to 104.0%, the result is pretty good.