DOI: https://doi.org/10.55373/mjchem.v25i3.54

Keywords: Online solid phase extraction-liquid chromatography; Response Surface Methodology; Box-Behnken Design; non-steroidal anti-inflammatory; tetracyclines; water samples

Abstract

The solid online phase extraction-liquid chromatography (SPE-LC) method was developed and validated for the simultaneous determination of non-steroidal anti-inflammatory drugs (NSAIDs) and Tetracyclines (TCs) from water samples. The selected NSAIDs and TCs were diclofenac (DIC), naproxen (NAP), acetaminophen (ACE) and oxytetracycline (OTC), doxycycline (DOC). Several essential parameters of valve switching time, acidified water and flow rate were optimised using the Box-Behnken Design (BBD) of Response Surface Methodology (RSM). Results were achieved under optimised conditions of 0.71 min valve switching time, 0.1 % acidified water and 0.78 mL min-1 flow rate of the mobile phase. Under optimised conditions, the method shows good linearities with the coefficient of determination (R2) in the range of 0.9990-0.9997 and low limits of detection (LOD) ≤ 0.73 mg L-1. The method was applied to the analysis of water samples with good relative recoveries in the range 94.4% - 108.3% and relative standard of deviation (RSD) ≤ 3.67 (n=3). The proposed method showed good selectivity and was sensitive to the simultaneous extraction of NSAIDs and TCs. Hence, it can be concluded that the online SPE LC is rapid, simple and has high extraction efficiencies.