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PubMed · 9884198

Solid phase micro extraction coupled with semi-microcolumn high performance liquid chromatography for the analysis of benzodiazepines in human urine.

K Jinno·M Taniguchi·M Hayashida
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Abstract

SPME/semi-microcolumn HPLC (SPME/LC) was investigated to analyze benzodiazepines in human urine samples. SPME conditions such as extraction time, extraction temperature, salt concentration and pH of matrix, flush volume and desorption time were optimized by extracting various drugs from a prepared water matrix. Combination of adding saturated salts to the matrix and controlling pH ranged from neutral to weakly alkaline conditions makes the increase of extraction efficiency. Under optimal condition SPME/LC is more sensitive than direct HPLC analysis without the SPME process. The limits of detection (LODs) was several ppb level and the relative standard deviation (RSD) was < 15% when human urine samples were analyzed by this analytical system. The system is very useful and is enough to assay benzodiazepines in a human urine sample without tedious and complex analytical procedures. In this paper the applicability of SPME/LC to the analysis of benzodiazepines in human urine samples was reported. In addition, the extension to the evaluation of SPME/LC/MS system was also described.

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BenzodiazepinesChemistry Techniques, AnalyticalChromatography, High Pressure LiquidHumansHydrogen-Ion ConcentrationIn Vitro TechniquesSensitivity and SpecificityJournal Article

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K Jinno, M Taniguchi, M Hayashida. 1998-09-01. Solid phase micro extraction coupled with semi-microcolumn high performance liquid chromatography for the analysis of benzodiazepines in human urine.. https://doi.org/10.1016/s0731-7085(98)00074-0

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