AbstractA fluorometric assay is described for sulfide ions determination. It is based on the finding that the oxidation of the non-fluorescent substrate thiamine (TH) by Cu(II) in basic solution to form fluorescent thiochrome is inhibited by sulfide ions. This results in a decrease in fluorescence intensity which is proportional to the concentration of sulfide ions. Under the optimized conditions, the decrease in fluorescence, best measured at excitation/emission wavelengths of 370/440 nm, decreases linearly in the 0.03 to 2.5 μM sulfide ions concentration range. The detection limit is 20 nM. The method shows excellent selectivity over many potentially interfering ions and has been successfully applied to the determination of sulfide ions in spiked tap water, lake water and the synthetic wastewater samples. The method is time-saving and environmentally friendly, and in our perception shows a great potential in water quality inspection and environmental monitoring. Graphical abstractA fluorescent assay for sulfide ions detection is proposed based on its inhibitory effect on the oxidation of thiamine by Cu(II) ions.

中文翻译：

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荧光法测定硫化物离子通过其对 Cu(II) 离子氧化硫胺素的抑制作用

摘要描述了一种用于测定硫化物离子的荧光测定法。它基于以下发现，即非荧光底物硫胺素 (TH) 在碱性溶液中被 Cu(II) 氧化形成荧光硫色素受到硫化物离子的抑制。这导致荧光强度的降低，这与硫化物离子的浓度成正比。在优化条件下，在 0.03 至 2.5 μM 硫化物离子浓度范围内，最好在 370/440 nm 激发/发射波长下测量荧光降低。检测限为 20 nM。该方法对许多潜在干扰离子显示出优异的选择性，并已成功应用于测定加标自来水、湖水和合成废水样品中的硫化物离子。该方法省时、环保，在我们的认知中显示出在水质检测和环境监测方面的巨大潜力。图形摘要基于硫胺素被 Cu(II) 离子氧化的抑制作用，提出了一种用于硫化物离子检测的荧光测定法。