title: Determination of ropivacaine in human plasma using highly selective molecular imprint-based solid phase extraction and fast LC-MS analysis.
abstract: A method for determining ropivacaine in human plasma using highly selective molecular imprint-based solid phase extraction and LC-MS analysis was developed. The imprinted extraction material was prepared using a structural analogue of ropivacaine as the template. The efficient sample cleanup achieved allowed single MS mode operation and analytical separation under isocratic conditions with a total separation time of less than two minutes. The absence of ion suppression was confirmed for both the m/z of ropivacaine and the m/z of the internal standard. The solid phase extraction protocol was optimised for elution of ropivacaine in a small volume of aqueous-rich solvent suitable for injection into a reversed phase LC-MS system. The final method measured trace levels of ropivacaine in human plasma with a limit of quantification of 2.5 nmol/L and interassay accuracy and precision of 101.7-104.4% and 2.1-7.2%, respectively.
authors.affiliation: Bioscience, AstraZeneca R&D Södertälje, 151 85, Södertälje, Sweden.
authors.forename: Zoe
authors.initials: Z
authors.lastname: Cobb
authors.forename: Lars I
authors.initials: LI
authors.lastname: Andersson
mesh_terms: D000577:Amides / Q000097:blood*; D002853:Chromatography, Liquid / Q000379:methods*; D006801:Humans; D013058:Mass Spectrometry / Q000379:methods*; D015394:Molecular Structure; D000077212:Ropivacaine; D012680:Sensitivity and Specificity; D013997:Time Factors; D014316:Tritium
chemical_list: D000577:Amides; D014316:Tritium; D000077212:Ropivacaine