TY - JOUR AU - Awni, W, M AB - Abstract This is an assay for labetalol in plasma by "high-performance" liquid chromatography, with 5-(2-[4-(4-chlorophenyl)ethyl]) salicylamide hemihydrate as the internal standard. Plasma samples (500 microL) are extracted with acetonitrile, evaporated under nitrogen, reconstituted in the mobile phase, and injected onto a PRP-1 (Hamilton) column packed with particles of poly(styrene-divinylbenzene) copolymer. Fluorescence, enhanced by post-column introduction of NH4OH, was measured in the effluent (excitation wavelength 340 nm, emission wavelength 418 nm). Retention times for labetalol and the internal standard were 1.99 and 3.32 min, respectively. Inter- and intraday CVs for high and low concentrations of the drug were less than 7.5%. The assay standard curve is linear from 1 to 250 micrograms/L. Some commonly co-administered drugs were tested and did not interfere. This content is only available as a PDF. © 1987 The American Association for Clinical Chemistry, Inc. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model) TI - Improved liquid-chromatographic assay of labetalol in plasma. JF - Clinical Chemistry DO - 10.1093/clinchem/33.8.1450 DA - 1987-08-01 UR - https://www.deepdyve.com/lp/oxford-university-press/improved-liquid-chromatographic-assay-of-labetalol-in-plasma-2XL0wVZOZ2 SP - 1450 EP - 1452 VL - 33 IS - 8 DP - DeepDyve ER -