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PubMed · 12862369

Determination of dissolved thiols using solid-phase extraction and liquid chromatographic determination of fluorescently derivatized thiolic compounds.

Degui Tang·Martin M Shafer·Kou Vang·Dawn A Karner·David E Armstrong
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Abstract

A method employing solid-phase extraction coupled with HPLC separation of thiol-monobromobimane (mBBr) derivatives was developed and optimized to quantify dissolved thiols at concentrations as low as 0.1 nM for glutathione (GSH) and gamma-glutamylcysteine (gammaEC) in natural waters. The reducing reagent, tri-n-butylphosphine (TBP), is needed for complete derivatization. At the optimal addition of TBP ([TBP]/[mBBr] = -0.4-1.6), no interference from copper was observed. The thiol fluorescence signal was totally suppressed if the mole ratio of TBP to mBBr was 2.6 or greater. Consistent recovery of thiols standards in a NaCl solution (0.5 M) was obtained using the Waters HLB reversed-phase resin, and blank levels of GSH and gammaEC were extremely low (less than 0.03 nM). The detection limits for GSH, gammaEC and phytochelatin-2 (PC-2) were 0.03, 0.03, and 0.06 nM, respectively.

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Chromatography, High Pressure LiquidFluorescent DyesKineticsReference StandardsSpectrometry, FluorescenceSulfhydryl CompoundsTemperatureJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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Degui Tang, Martin M Shafer, Kou Vang, Dawn A Karner, David E Armstrong. 2003-05-23. Determination of dissolved thiols using solid-phase extraction and liquid chromatographic determination of fluorescently derivatized thiolic compounds.. https://doi.org/10.1016/s0021-9673(03)00639-3

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