Two-phase hollow fiber liquid phase microextraction for preconcentration of naproxen prior to UV-Vis spectrophometr

Naproxen (NAP) is a non-steroidal anti-inflammatory drug (NSAID) which is used for the treatment of intense pain and inflammation. Several analytical methods have been published for the determination of NAP in pharmaceutical preparations and biological fluids. These methods included Capillary electrophoresis with electro spray mass spectrometry, HPLC and capillary isotachophoresis. To obtain accurate, reliable and sensitive results, a sample preparation is required prior to detection. The traditional techniques are characterized by long analytical time, manual manipulation of the extracts, large consumption of sample and reagents and produces of large amounts of waste. It has been proved that hollow fiber liquid phase microextraction (HF-LPME) is very useful for extraction of drugs and metabolites from biological matrices and pollutants from environmental samples with simultaneous clean-up of the matrices [1]. HF-LPME, a relatively new miniaturized technique, has high enrichments, simplicity, rapidity and low consumption of organic toxic solvents [2]. The characteristics of NAP show that it has low polarity and consequently has better extraction efficiency in nonpolar solvents. Therefore, a two-phase HF-LPME system has been designed for preparation of pharmaceutical and urine samples followed by spectrophotometric analysis of NAP. The effective parameters of the method, such as extracting organic solvent (acceptor phase), pH of sample solution (donor phase), extraction time, stirring speed, and ionic strength were optimized. Under optimum experimental conditions, the calibration curve was linear in the concentration range of 0.05–10 µM NAP. Limits of detection and quantification were found to be 0.02 and 0.0.07 µM NAP, respectively. The method was successfully applied for determining of naproxen in some pharmaceutical and urine samples.