催化H_2O_2氧化2,3,4,9-四氢-9-羟基-1,10-蒽醌荧光猝灭法测定痕量砷

Determination of Trace Arsenic by Fluorescence Quenching Method Based on Catalysis of Hydrogen Peroxide Oxidizing 2,3,4,9-tetrahydro-9-hydroxy-1,10-anthraquinone

基于HCl介质中和α，α-联吡啶存在下，As（V）可催化H2O2氧化2，3，4，9-四氢-9-羟基-1，10-蒽醌（R）转化无荧光化合物，导致体系荧光急剧猝灭，据此建立了催化H2O2氧化R荧光猝灭法测定痕量砷的新方法．在最佳条件下，As（V）含量在0．0040～0．4000ng／mL范围内与荧光光强度的△If值符合比尔定律，工作曲线的回归方程△If=11．94＋233．7 CAs（v）（ng／mL），n=7，相关系数r=0．9994，检出限为6．2×10^-13。gAs（V）／mL，n=11．对0．0040和0．4000ng／mL As（V）分别进行11次的测定，其RSD为2．6％与3．8％．该方法重现性好、灵敏、准确，用于实际中砷含量的测定，结果满意．还报道了R的合成，并借助核磁共振谱、红外光谱及质谱等谱学方法确定了其结构．

A new fluorescence quenching method for the determination of trace As（V） has been established. Based on the facts that in HCl solution with α, α＇-dipyridine. As（V） can catalyze the reaction of H2O2 oxidizing 2,3,4,9-tetrahydrogen-9-hydroxy-1,10-anthraquinone （R） to form non-fluorescence complex which cause the fluorescence quenching. Under the optimum condition, the relationship between the △If of the emitting intensity and the content of 0. 0040-0. 400 0 ng/mL As（V） conform to Beer＇ law. The regression equation of working curve can be expressed as △If= 11. 94 ＋ 2 3 3. 7 CAs（V） （ng/mL） （r=0. 9994, n= 7）. The limit detection （LD） is 6.2×10^-13 g As（V）/mL （n=11）. The sample containing 0. 0040 and 0.400 0 ng/mL As（V） are repeatedly determined for 11 times. RSD are 2.6% and 3.8% respectively. This method has good repeatability, sensitivity and high precision. It has been successfully applied to the determination of trace As（V） in real samples with satisfactory results. The structure of synthesized was determined by ^1H-NMR , IR and MS spectroscopy.