Rapid Removal of Template from Molecularly Imprinted Polymers by Accelerated Solvent Extraction

Abstract

A novel extraction method to remove template from molecularly imprinted polymer (MIP) and reduce template bleeding using accelerated solvent extraction (ASE) has been developed. The MIP was synthesized following a noncovalent protocol using nicotine as the template molecule, methacrylic acid as the functional monomer, and ethylene glycol dimethacrylate as the cross-linker. After optimizing the extraction solvent and temperature, the method was carried out to remove template from nicotine MIP at 80°C with 300 ml of methanol-acetic acid (90:10, v/v), and the extraction efficiency of nicotine template from MIP was 94.2%. The extraction procedure was completed in 70 min. After the treatment, the imprinted polymers were packed into solid-phase extraction columns and the bleeding amount of nicotine template was estimated by quantifying the amount of template released in 10 ml of methanol-acetic acid (90:10, v/v). In this case, a bleeding level of 9.8μg l −1 was found. Compared with the traditional template removing methods, soxhlet extraction and ultrasonic assisted extraction, ASE was the more effective method aimed at rapid removal of template from molecularly imprinted polymer.