Analysis of biogenic thiols in natural water samples by high-performance liquid chromatographic separation and fluorescence detection with ammonium 7-fluorobenzo-2-oxa-1,3-diazole-4-sulfonate (SBD-F)


2000 Mar 9


Tang DG
Wen LS
Santschi PH

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A sensitive and reliable reversed-phase high-performance liquid chromatography (HPLC) method has been developed to analyze naturally occurring low-molecular weight thiols using pre-column derivatization with ammonium 7-fluorobenzo-2-oxa-1,3-diazole-4-sulfonate (SBD-F) and fluorescence detection in a gradient elution. The derivatization procedure and separation conditions were optimized by careful control of the reaction conditions in terms of time, temperature, pH and reducing agent. A linear calibration in the nM range was obtained for all the standard compounds, allowing measurement of thiols in natural water samples. Results show that the reducing agent tri-n-butylphosphine (TBP) not only acts as an anti-oxidant/disulfide cleaving agent, but also enables the SBD-F to react with thiols complexed by soft metals. This is the first study reported using the SBD-F labeling technique to measure phytochelatin concentrations. The methodology has been successfully applied to estuarine water samples from Galveston Bay. (C) 2000 Elsevier Science B.V. All rights reserved




water analysis, thiols, phytochelatin, soft metals, FLUORESCENCE DETECTION, PLASMA, copper, ALGAE