生物无机铁磁纳米粒子酶活性能研究

Peroxidase-like activity of bioinorganic ferromagnetic nanoparticles

采用酶标分析仪,在H2O2存在的情况下,研究了原核生物趋磁细菌天然合成的磁性纳米颗粒——磁小体具有内在的类似于过氧化物酶的酶活性能。结果显示,随着缓冲液的pH值、反应温度和H2O2浓度的增加,磁小体的所有酶活性能皆呈"抛物线"型变化,满足酶学中关于酶催化反应性能的解释。由此得出磁小体催化反应的最适pH是4.0值,最佳温度是30℃,最佳H2O2浓度是0.28mol/L。随后,进一步考察了磁小体的酶活稳定性。结果显示在pH值从0.2～12.9变化的不同缓冲液浸泡2h之后的磁小体的类酶活性保持在60%以上;从4～97℃不同温度孵育磁小体2h,磁小体的类酶活性没有明显下降。所有结果表明处理之后的磁小体仍能保持优异的酶催化稳定性。

The effect of an intrinsic peroxidase-like activity of magnetosomes synthesized by magnetotactic bacteria were studied in the presence of H2O2 by enzyme-mark analyzer.The results show that all curves of the catalytic activity of magnetosomes have parabolic-like changes and are in agreement with the enzymatic michaelis-menten equation with the pH,temperature and H2O2 concentration increasing.The pH 4.0,30℃ and 0.28mol/L H2O2 concentration were the optimal conditions of catalytic reaction.Subsequently,the stability of magnetosomes was further investigated.The peroxidase activities of magnetosomes incubated at a range of values of pH from 0.2 to 12.9 for 2h remained over 60% of the best performance.Similarly,after magnetosoes were incubated at temperatures between 4 to 97℃ for 2h,no obvious decrease of the catalytic activity was observed.All results suggested that the treated magnetosoes still remained the excellent stability.