Rapid determination of loratadine in small volume plasma samples by high-performance liquid chromatography with fluorescence detection.
A simple and rapid high-performance liquid chromatographic method with fluorescence detection was developed for the determination of loratadine in small volume plasma samples. Liquid-liquid extraction of loratadine and diazepam (as internal standard) from plasma samples was performed with n-butyl alcohol/n-hexane (2:98, v/v) in alkaline condition followed by back-extraction into diluted perchloric acid. Chromatography was carried out using a C8 column (250 x 4.6 mm, 5 microm) under isocratic elution with acetonitrile-20 mM sodium dihydrogen phosphate-triethylamine (43:57:0.02, v/v), pH 2.4. Analyses were run at a flow-rate of 1.0 ml/min at room temperature. The method was specific and sensitive with a quantitation limit of 0.62 ng/ml and a detection limit of 0.2 ng/ml at a signal-to-noise ratio of 3:1. The mean absolute recovery of loratadine from plasma was 84%, while the intra-and inter-day coefficient of variation and percent error values of the assay method were all less than 9.7%. Linearity was assessed in the range of 0.62-20 ng/ml in plasma with a correlation coefficient of greater than 0.999. The method has been used to analyze several hundred human plasma samples for bioavailability studies.
Amini
Hossein
H
Department of Pharmacology, Neuroscience Research Center, Shaheed Beheshti University of Medical Sciences, P.O. Box 19835-355, Tehran, Iran.
Ahmadiani
Abolhassan
A
D002138:Calibration; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D039563:Histamine H1 Antagonists, Non-Sedating / Q000097:blood*; D006801:Humans; D017336:Loratadine / Q000097:blood*; D012015:Reference Standards; D015203:Reproducibility of Results; D013050:Spectrometry, Fluorescence / Q000379:methods*
D039563:Histamine H1 Antagonists, Non-Sedating; D017336:Loratadine