A RAPID, SENSITIVE, AND ENVIRONMENTALLY FRIENDLY ON-LINE SOLID PHASE EXTRACTION USING PROTEIN-COATED μ-BONDAPAK CYANIDE SILICA PRECOLUMN FOR CHROMATOGRAPHIC DETERMINATION OF PARACETAMOL IN HUMAN SERUM

Abstract

A simple, rapid, and sensitive green high-performance liquid chromatographic (HPLC) method with automated precolumn extraction has been developed and evaluated for analysis of paracetamol (PC) in human serum. The method is performed by direct injection of serum samples onto a homemade protein-coated μ-Bondapak CN silica precolumn, where PC is preconcentrated and retained while proteins and very polar components are washed to waste using a phosphate buffer saline, pH 7.4. The trapped drug is then back-flushed from the precolumn by column-switching followed by separation on a Thermo Scientific Hypersil ODS analytical column with an environmentally friendly mobile phase consisting of ethanol and phosphate buffer (0.01 M, pH 3.5) in the ratio of 5:95 (v/v). Detection is performed at 254 nm. The chromatographic procedure yields precise results and is able to run one sample in only 6 min. The calibration curve is linear over the concentration range of 10–10000 ng mL−1 PC. The applicability of the method was successfully evaluated by monitoring the concentration of PC in human serum after an oral administration of 500 mg.