【摘要】 吡红B在氯化血红素催化下可被过氧化氢氧化而使其荧光猝灭。在pH 5 .2弱酸性介质中 ,稳态催化速率由模拟酶和底物浓度决定 ,催化体系服从Michaelis Menten方程 ,用Lineweaver Burk作图法求得米氏常数 1.4× 10 - 5mol L ,最大反应速度 1.9× 10 - 6mol L·s ;催化常数 2 5 .6 /s。在最佳反应条件下 ,荧光猝灭程度F0 F与过氧化氢浓度在 0 .0～ 7.2× 10 - 7mol L范围内呈线性关系 ;检出限为 8.0× 10 - 9mol L。当与葡萄糖氧化酶联用时 ,可定量检测葡萄糖 ,线性关系为 (0 .0～ 1.0 )× 10 - 5mol L ;检出限为 3.3× 10 - 8mol L。方法用于分析人血清中葡萄糖含量 ,结果与苯酚 4 氨基安替比林法一致。更多还原

【Abstract】 Pyronine B(tetraethyldiaminoxanthenyl chloride,PB)was used as a fluorogenic substrate for the determination of hydrogen peroxide and glucose based on the catalytic effect of hemin as mimic-enzyme of horseradish peroxidase. The fluorescence of pyronine B was quenched by hydrogen peroxide in the presence of hemin at pH 5.2. The steady-state catalytic rate depends upon mimic-enzyme and substrate concentrations, and the Michaelis-menten parameters K m, V max and K cat are 1.4×10 -5 mol/L, 1.9×10 -6 mol/L·s and 25.6/s, respectively. Under optimum conditions, linear relationship between the fluorescence quenching (F 0/F) and the concentration of hydrogen peroxide was observed in the range of 0.0 to 7.2×10 -7 mol/L. The limit of detection (3σ) was 8.0×10 -9 mol/L. By coupling with glucose oxidase-catalytic reaction, glucose was quantified in the linear range of 0.0 to 1.0×10 -5 mol/L with the limit of detection (3σ) of 3.3×10 -8 mol/L. The determination results of glucoses in human serum are in agreement with those by the phenol-4-aminoantipyrine method.更多还原