title: Large volume injection of 1-octanol as sample diluent in reversed phase liquid chromatography: application in bioanalysis for assaying of indapamide in whole blood.
abstract: Large volume injection of samples in strong diluents immiscible with the mobile phases used in reversed phase liquid chromatography (RPLC) has been recently introduced in practice. In the present work, the potential of the technique has been evaluated for bioanalytical applications. The process consists of the liquid-liquid extraction of indapamide from whole blood into 1-octanol, followed by the direct injection from the organic layer into the LC. Detection was made through negative electrospray ionization (ESI) and tandem mass spectrometry (MS(2)). The method was developed, validated, and successfully applied to a large number of samples in two bioequivalence studies designed for indapamide 1.5mg sustained release and 2.5mg immediate release pharmaceutical formulations. The performance of the analytical method is discussed based on data resulting from the validation procedure and the completion of the bioequivalence studies.
authors.affiliation: Bioanalytical Laboratory, SC Labormed Pharma SA, #44B Th. Pallady Blvd, Bucharest 032266, Romania.
authors.forename: Stefan
authors.initials: S
authors.lastname: Udrescu
authors.forename: Iulia Daniela
authors.initials: ID
authors.lastname: Sora
authors.forename: Florin
authors.initials: F
authors.lastname: Albu
authors.forename: Victor
authors.initials: V
authors.lastname: David
authors.forename: Andrei
authors.initials: A
authors.lastname: Medvedovici
mesh_terms: D020003:1-Octanol / Q000737:chemistry*; D002853:Chromatography, Liquid / Q000295:instrumentation / Q000379:methods*; D018592:Cross-Over Studies; D003692:Delayed-Action Preparations; D004305:Dose-Response Relationship, Drug; D016903:Drug Monitoring / Q000379:methods*; D004867:Equipment Design; D006801:Humans; D007190:Indapamide / Q000008:administration & dosage / Q000097:blood*; D007202:Indicators and Reagents; D015203:Reproducibility of Results; D012995:Solubility; D012996:Solutions; D013810:Therapeutic Equivalency
chemical_list: D003692:Delayed-Action Preparations; D007202:Indicators and Reagents; D012996:Solutions; D007190:Indapamide; D020003:1-Octanol