Application of DLLME to Isolation and Concentration of Non-Steroidal Anti-Inflammatory Drugs in Environmental Water Samples

Dispersive liquid-liquid microextraction (DLLME) coupled with liquid chromatography-tandem mass spectrometry detection was applied for determination of selected anti-inflammatory pharmaceuticals: ibuprofen, ketoprofen, naproxen and diclofenac. Development of DLLME procedure included optimisation of several important parameters such as kind and volume of extracting and dispersive solvents as well as sample pH. Under optimised conditions a two-step extraction with sonication was used. Chloroform was applied as the extracting and acetone as dispersing solvent. Calibration curves ranges were 1-500 mu g L-1 for naproxen and ibuprofen and 0.25-500 mu g L-1 for ketoprofen and diclofenac with correlation coefficients at least 0.997. Limits of quantitation were from 0.5 to 10 ng L-1. The developed analytical method was employed for determination of ibubrofen, ketoprofen, naproxen and diclofenac in river and tap water samples. The results showed that DLLME is a simple, rapid and sensitive analytical technique for the pre-concentration of trace amounts of pharmaceuticals in environmental water samples.