The Electrochemical Sensor for Selective Solid Phase Extraction of Pseudoephedrine Hydrochloride in a Real Sample

In the current study, a new technique was developed for quantification and qualification of pseudoephedrine hydrochloride (PSE) in a real sample, which was based on electrochemical sensors and molecular imprinted polymer (MIP). The carbon paste electrode (CPE) was modified and optimized by a different ratio of MIP. MIP/CPE was used as the extraction and working electrode. Differential pulse voltammetry (DPV) method was utilized for measurement. The MIP (molecularly imprinted polymer) and NIP (non-imprinted polymer) were synthesized by various ratios of functional monomer (methacrylic acid) and cross-linker (ethylene glycol dimethacrylate) and template (pseudoephedrine hydrochloride). Some parameters such as pH, extraction time, MIP/CP ratio, stirring rate, and concentration of sample were optimized, and under these conditions, the oxidation peak current was proportional to the pseudoephedrine hydrochloride concentration over a range of 10-500 µM with the coefficient of determination 0.992 (R2). The limit of detection (LOD) was found about 0.274 µM and the limit of quantification (LOQ) was located about 0.825 µM. The relative standard deviation (RSD) was about 1.17%. The results indicated that the modified electrode had a specific ability in selective extraction of pseudoephedrine hydrochloride. Keywords