催化过氧化氢氧化罗丹明B-四苯硼化钠荧光猝灭法测定痕量钼  

Determination of Trace Molybdenum by Fluorescence Quenching Method Based on Catalytic Effect of H_2O_2 on Formation of Ion Association Complex [Rhod.B]^+.B[(C_6H_6)_4]^-

作　　者：刘佳铭[1] 黄丽钗[1] 陈芳[1] 林彬彬[1] 

机构地区：[1]漳州师范学院化学与环境科学系,福建漳州363000

出　　处：《漳州师范学院学报（自然科学版）》2008年第3期60-63,共4页Journal of ZhangZhou Teachers College（Natural Science)

摘　　要：基于HCl介质和90℃加热10min的条件下,罗丹明B(Rhod.B)与四苯硼化钠(NaB(C6H6)4)作用生成的[Rhod.B]+.[B(C6H6)4]-离子缔合物能发射强而稳定的荧光,[Rhod.B]+.[B(C6H6)4]被H2O2氧化而发生荧光猝灭,Mo(VI)能催化H2O2氧化[Rhod.B]+.[B(C6H6)4]的反应,导致其荧光剧烈猝灭,且△F与Mo(VI)含量呈线性关系,据此建立了催化H2O2氧化[Rhod.B]+.[B(C6H6)4]离子缔合物荧光法测定痕量钼的新方法.本法的线性范围为4.00～400(pg/L),工作曲线的回归方程为△F=67.27.+0.3243 CMo(VI)(pg/L),n=6,相关系数r=0.9981,检出限(LD)为0.92pg/L.用于实际样品中痕量Mo(VI)的测定,结果满意.同时探讨了离子缔合物荧光法定痕量钼的反应机理.A new fluorescence quenching method for the determination of trace molybdenum has been established. It is based on the fact that in HCI medium, Rhod.B^＋（ rbodamine B） ion can react with NaB（C6H6）4 to form ion association complex [Rhod.B]^＋-B[（C6H6）4]^-, which can emit strong and stable fluorescence when the system is heated at 90℃ for 10 minutes. And the presence of H2O2 can oxidize [Rhod.B]^＋-B[（C6H6）4]^- to cause the fluorescence quenching, while molybdenum can catalyze H2O2 to oxidative the ion association complex to quench the fluorescence severely. The linear dynamic range of this method is 4.00-400pg/L with a detection limit （L.D.） of 0.92pg/L and the regression equation of working curve is AF = 67.05 ＋ 0.3250 CMo（VI） （pg/L）, n = 6, r = 0.9980. This method has been applied to the determination of trace molybdenum in real samples with special feature such as wide linear dynamic range, high sensitivity and good selectivity. The reaction mechanism for formation of ion association complex is also discussed.

关 键 词：MO(VI) 罗丹明B-四苯硼化钠离子缔合物 催化荧光法 

分 类 号：O629.8[理学—有机化学]