Sensitive assay for measuring amoxicillin in human plasma and middle ear fluid using solid-phase extraction and reversed-phase high-performance liquid chromatography.

Z Yuan; H Q Russlie; D M Canafax

doi:10.1016/0378-4347(95)00302-1

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Sensitive assay for measuring amoxicillin in human plasma and middle ear fluid using solid-phase extraction and reversed-phase high-performance liquid chromatography.

Z Yuan·H Q Russlie·D M Canafax

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Abstract

We developed a sensitive assay to measure amoxicillin in human plasma and middle ear fluid (MEF) using solid-phase extraction and reversed-phase HPLC. Amoxicillin and cefadroxil, the internal standard, were extracted from 50-200 microliters of sample with Bond Elut C18 cartridges. The extract was analyzed on a 15 cm x 2 mm, 5 micron Keystone MOS Hypersil-1 (C8) column with UV detection at 210 nm. The mobile phase was 6% acetonitrile in 5 mM phosphate buffer (pH = 6.5) and 5 mM tetrabutylammonium. The average absolute recovery of amoxicillin and cefadroxil were 91.2 +/- 16.6% and 91.0 +/- 6.8%, respectively. The limit of quantitation was 0.125 microgram/ml with 200 microliters sample size. The linear range was from 0.125 to 35.0 micrograms/ml with correlation coefficients greater than 0.999. These analytic conditions produced a highly sensitive amoxicillin assay in human body fluids without derivatization.

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Acetonitriles Amoxicillin Body Fluids Calibration Cefadroxil Chromatography, High Pressure Liquid Detergents Ear, Middle Exudates and Transudates Humans Otitis Media with Effusion Quaternary Ammonium Compounds Reproducibility of Results Sensitivity and Specificity Spectrophotometry, Ultraviolet Journal Article Research Support, U.S. Gov't, P.H.S.

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Z Yuan, H Q Russlie, D M Canafax. 1995-12-01. Sensitive assay for measuring amoxicillin in human plasma and middle ear fluid using solid-phase extraction and reversed-phase high-performance liquid chromatography.. https://doi.org/10.1016/0378-4347(95)00302-1

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