A fast and feasible microextraction by packed sorbent (MEPS) procedure for HPLC analysis of the atypical antipsychotic ziprasidone in human plasma

An original high-performance liquid chromatographic method coupled to microextraction by packed sorbent (MEPS) was developed for the therapeutic drug monitoring (TDM) of psychiatric patients treated with the recent atypical antipsychotic ziprasidone. The chromatographic separation was achieved on a RP C18 column, using an isocratic mobile phase and setting the wavelength at 320 nm. The analyte was extracted from human plasma by means of a fast and feasible innovative MEPS procedure, optimised on C2 sorbent and requiring only 100 µL of biological sample. A second pre-treatment procedure, based on solid phase extraction (SPE), has been also developed for comparison. The availability of different pre-treatment procedures allows the choice of the one best suiting the specific clinical, economic and scientific needs. The extraction yield values were always higher than 90% and sensitivity was also good, with a limit of quantitation (LOQ) of 1 ng/mL. The method was successfully applied to plasma samples from ten subjects undergoing therapy with ziprasidone, thus confirming its suitability for the TDM of psychiatric patients, in order to personalise their pharmacological treatments.