Preparation and application of novel thermo-sensitive molecularly imprinted polymer for selective extraction of omeprazole from pharmaceutical formulation and biological fluids

Abstract

ABSTRACT Omeprazole selective molecularly imprinted polymer was synthesized by polymerization using 2-hydroxyethyl methacrylate as a monomer, N-vinylcaprolactam as a thermo-sensitive polymer, and N, N′-methylenebisacrylamide as cross-linker, respectively. This study aimed to develop a novel polymer as a nanoadsorbent for the extraction of omeprazole in biological and pharmaceutical samples. To achieve maximum extraction recovery of the drug, the Nd:YAG pulsed laser irradiation was used to convert adsorbent particles into smaller sizes using water solvent at different irradiation times. Properties of prepared thermo-sensitive molecularly imprinted polymer were characterized by different analyses. The optimal extraction conditions were thermo-sensitive molecularly imprinted polymer dosage of 0.01 g, a cross-linking agent of 0.15 g, contact time of 15 min, eluent of methanol, the temperature of 25°C, initial drug concentration of 20 mg L−1, and solution pH of 4. The sorption isotherms and selective recognition of thermo-sensitive molecularly imprinted polymer were investigated in detail. Sorption results fitted well into the linearized Langmuir equation. The selectivity experiment has shown that the sorption capacity and selectivity of thermo-sensitive molecularly imprinted polymer to omeprazole were higher than those of bicalutamide and prednisolone. A high-performance liquid chromatography-ultra-violet detector method was validated and utilized for analysis of drug extracted from biological and pharmaceutical samples. The method was linear in the range of 0.5–80 mg L−1 with a relative standard deviation value of 0.094 and a limit of detection and a limit of quantification of 0.9 and 30 µg L−1, respectively. The recovery of omeprazole drug ranged from 94.3%, 99.2%, and 98.1%, respectively, in human plasma, human urine, and pharmaceutical samples.