Stir-membrane liquid microextraction for the determination of paracetamol in human saliva samples

Abstract

Background: In this article, stir-membrane liquid microextraction is adapted for the analysis of volume-limited biological samples, using as a model analytical problem the determination of paracetamol in human saliva by LC with UV. A three-phase microextraction mode is used for the extraction of the target analyte, taking advantage of its acid–base properties. Results: All the variables involved in the extraction have been studied and optimized in depth. The method has been analytically characterized on the basis of its linearity, sensitivity and precision. The LOD is 0.5 µg/l while the repeatability, expressed as RSD, is better than 14.2 %. A tenfold preconcentration factor was obtained, which involves an absolute recovery value of 25%. Moreover, the relative recovery is very close to the 100%. Conclusion: Finally, the proposed method has been used to perform a PK study of paracetamol.