Comorbid Panic Symptoms And Relation With Clinical Correlates In Schizophrenia

Amisulpride (SOLIAN) belongs to the benzamide series and shows antischizophrenic and antidepressant (antidysthymic) properties in man. Two methods suitable for pharmacokinetic investigations are proposed for the determination of amisulpride in human plasma. For the liquid-liquid extraction (LLE) based method, the plasma, added with the internal standard (an amisulpride analogue) is alkalinised with NaOH and extracted with a diethyl ether-chloroform mixture. The organic phase is removed, evaporated to dryness and redissolved in an acidic phosphate-acetonitrile mixture that, after a back-washing step with n-hexane, is injected onto the HPLC column (C18 BDS type) connected with a fluorimetric detector. The second method is based on an automatic solid-phase extraction (SPE) performed on an ASPEC device. The plasma sample, diluted with a pH 9 borate buffer, is loaded onto a disposable SPE C18 100-mg column. The analytes of interest (amisulpride and internal standart), after two washing steps with different solvents, are recovered in pure methanol; after evaporation to dryness, the residue is dissolved in an acidic phosphate buffer and injected onto the chromatographic apparatus already described. The limit of quantitation (LOQ) is 0.5 ng ml−1 for both methods; a linear correlation between concentrations and detector response has been demonstrated in the range 0.5–640 ng ml−1 for LLE, which is the most used method; for SPE methods, less used, linearity has been assessed in the plasma range of 0.5–160 ng ml−1.