title: Liquid chromatographic analysis of the cis(Z)- and trans(E)-isomers of clopenthixol in human plasma using a novel solid phase extraction procedure.
abstract: A simple and highly sensitive high-performance liquid chromatographic (HPLC) method for the simultaneous determination of cis(Z)-clopenthixol and trans(E)-clopenthixol in human plasma has been developed. The chromatographic analysis was carried out isocratically on a reversed-phase column (C(8) 150 x 4.6 mm I.D., 5 microm) using a mixture of 25 mM phosphate buffer and acetonitrile (65:35 v/v, pH* 3.0) as the mobile phase, and ultraviolet detection at 230 nm. Plasma sample pretreatment was accomplished by means of an original solid-phase extraction (SPE) procedure carried out on cyanopropyl cartridges, with a high extraction yield and good selectivity. Under the optimum conditions, calibration graphs of spiked human plasma samples were obtained over the concentration ranges 1-300 ng ml(-1) for cis(Z)-clopenthixol and 1-200 ng ml(-1) for trans(E)-clopenthixol. The limit of detection (LOD) was 0.3 ng ml(-1) for both cis(Z)- and trans(E)-isomers of clopenthixol. The method was successfully applied to the determination of cis(Z)-clopenthixol and trans(E)-clopenthixol in plasma samples of schizophrenic patients undergoing therapy with zuclopenthixol.
authors.affiliation: Department of Pharmaceutical Sciences, University of Bologna, Via Belmeloro 6, 40126 Bologna, Italy.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Pucci
authors.forename: Francesca
authors.initials: F
authors.lastname: Bugamelli
authors.forename: Roberto
authors.initials: R
authors.lastname: Mandrioli
authors.forename: Claudio
authors.initials: C
authors.lastname: Bartoletti
authors.forename: Nicola
authors.initials: N
authors.lastname: Rossi
authors.forename: Maria Augusta
authors.initials: MA
authors.lastname: Raggi
mesh_terms: D014150:Antipsychotic Agents / Q000097:blood* / Q000737:chemistry; D002138:Calibration; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D003006:Clopenthixol / Q000097:blood* / Q000737:chemistry; D006801:Humans; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013237:Stereoisomerism
chemical_list: D014150:Antipsychotic Agents; D003006:Clopenthixol