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PubMed · 8634752

Rapid, specific and sensitive method for isoniazid determination in serum.

N Sadeg·N Pertat·H Dutertre·M Dumontet
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Abstract

An original simple, specific and rapid high-performance liquid chromatographic assay for the determination of isoniazid (INH) in human serum is presented. The drug was extracted from the serum by protein precipitation with 30% (w/v) trichloroacetic acid, then the drug was reacted with the coupling reagent, trans-cinnamaldehyde, to form a derivative absorbing at 340 nm. A 20-microliters aliquot was injected into the chromatograph after neutralization with 1 M KOH solution. A liquid chromatograph equipped with a reversed-phase 30-microns C18 precolumn linked to a 4-microns C18 analytical column was used. The drug was eluted with a mixture of acetonitrile-water-triethylamine-acetic acid (400:600:2:1, v/v), pH value was 5 +/- 1. Flow-rate and wavelength were set at 1 ml/min and 340 nm, respectively. The extraction recoveries from human serum averaged 100% for INH at concentrations of 1, 2 and 4 mg/l. The coefficients of variation for three different concentrations for INH in serum in the within-day study varied between 1.2 and 3.5%, whereas those in the day-to-day study varied between 2.8 and 4.3%.

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Antitubercular AgentsChromatography, High Pressure LiquidHumansIsoniazidReproducibility of ResultsSensitivity and SpecificitySpectrophotometry, UltravioletJournal Article

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N Sadeg, N Pertat, H Dutertre, M Dumontet. 1996-01-12. Rapid, specific and sensitive method for isoniazid determination in serum.. https://doi.org/10.1016/0378-4347(95)00336-3

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