过氧化物模拟酶催化氧化测定过氧化氢

Determination of Hydrogen Peroxide Catalyzedby Hemin as Mimetic Peroxidase

在 pH9．58 NH_4Cl－NH_3·H_2O缓冲体系中,氯化血红素(Hemin)呈现过氧化物酶的催化性能,催化过氧化氢氧化有机染料2,4－二羟基苯基荧光酮(2,3,7－tirhydroxy－9(3,5－dihydroxy)phenylfluorone,DHPF)降解褪色．本文研究了Hemin－DHPF－H_2O_2催化体系的褪色反应条件,拟定了测定H_2O_2高灵敏度的光分析方法,测定H_2O_2的线性范围为 0~2．40 × 10－5mol/L,表观摩尔吸光系数为8．06×10~3L·mol-1·cm-1,检测线为2．48×10~6mol·L-1．根据理论计算和实验现象,探讨了酶催化反应的可能反应机理．

In the presence of pH9. 58 NH4C1~NH3·H2O buffer solution, the catalytic property of hemin asmimetic peroxidase was exhibited on the gradation and discolor oxidation of 2, 4-dihydroxyphenylfluorone byhydrogen peroxide. The catalytic optimum condition for hemin-DHPF-H2O2 system was studied. The highlysensitive spectrophotometric analytic method of hydrogen peroxide was presented with 2. 48 × 10^(-6) mol/L de-tection limit. The detection range of hydrogen peroxide was 0-2. 4×10-5 mol/L with apparent molar absorp-tivity 8. 10×103L·mol-1·cm-1 of catalytic reaction. The possible catalytic reaction mechanism was dis-cussed on the basis of experimental results and data of calculation parameters.