【摘要】 采用酶催化动力学分析法研究了过氧亚硝酸的氧化行为,提出了一种催化荧光光谱测定过氧亚硝酸的新方法。根据肌红蛋白所具有的模拟酶性质催化过氧亚硝酸氧化酪氨酸,产生一种具有荧光特性的产物酪氨酸二聚体。在实验选定的最佳反应条件下,该产物的荧光强度与过氧亚硝酸阴离子(ONOO-)的浓度在6.00×10-7~3.00×10-5mol/L范围内呈良好的线性关系;方法检出限为8.20×10-8mol/L。用停流荧光光谱法研究了酶催化反应的动力学行为,探讨了反应的可能机理,认为酪氨酸的二聚体可能是ONOO-在体内造成损伤的另一标志物。更多还原

【Abstract】 A novel spectrofluorimetric method for the determination of peroxynitrite was proposed.The method is based on a mimetic enzyme catalyzed reaction with myoglobin as the catalyst and L-tyrosine as the substrate.A new fluorescent substance was produced that might probably be the coupled dimmer of tyrosine,which,（instead） of nitryl-tyrosine,was likely to be a new marking substance of ONOO^-injury in vivo.Kinetics of the reaction was studied by stopped-flow method and the possible reaction mechanism was also recommended.The optimum conditions of the determination were studied.The proposed method is simple and highly sensitive with a detection limit of 8.20×10⁸ mol/L of peroxynitrite.A linear ralationship is obtained over the peroxynitrite concentration range 6.00×10^-7 mol/L to 3.00×10^-5 mol/L with a correlation coefficient of 0.9971.更多还原