氧化石墨烯/L-色氨酸体系荧光光度法测定铋离子

Determination of Bismuth by Fluorescence Spectrophotometry with Graphene Oxide/L-Tryptophan System

在水溶液中,氧化石墨烯(GO)对L-色氨酸(L-Trp)具有荧光猝灭作用,但加入Bi3+后,体系的荧光增强,且增加程度与Bi3+的加入量有关。基于该现象,本研究建立了一种测定Bi3+的荧光分析新方法。考察了反应时间、反应温度、pH值、L-Trp浓度、GO加量、试剂加入顺序对荧光分析的影响。在最佳条件下,测定Bi3+的线性范围为0.5~100μmol·L-1(R2=0.9995),检出限为0.5×10-6 moL·L-1。该方法具有灵敏度高、速度快、成本低的优点,能应用于废水中Bi3+含量测定,结果令人满意。

In aqueous solution,graphene oxide(GO)had a fluorescence quenching effect to L-tryptophan(L-Trp).When Bi3+were added,the fluorescence of the system was enhanced,and the enhancement degree was related to the amount of Bi3+.In this work,the fluorescence spectrophotometry for the determination of Bi3+was established using the quenching mechanism of GO/L-Trp system.The effects of reaction time,reaction temperature,pH,L-Trp concentration,the amount of GO and reagent addition order on fluorescence analysis were investigated.Under the optimized conditions,the linear range of Bi3+was 0.5~100μmol/L which had a good linear relationship with the fluorescence intensity.The correlation coefficient was 0.9995,and the detection limit was 0.5×10-6 mol/L.The new method had the advantages of high sensitivity,high speed and low cost,and was successfully applied todetermine of Bi3+in wastewater samples.