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.
Department of Pharmacology, Neuroscience Research Center, Shaheed Beheshti University of Medical Sciences, P.O. Box 19835-355, Tehran, Iran.
Hossein
H
Amini
Abolhassan
A
Ahmadiani
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