纳米金对抗氧化剂的催化氧化及其活性的影响

Effect of gold nanoparticles on the catalytic oxidation and the activity of antioxidants

目的:探讨纳米金对抗坏血酸和表儿茶素氧化进程的影响及其生物学效应。方法:合成5 nm左右的金纳米颗粒,通过紫外可见光谱研究金颗粒加入前后两种抗氧化剂的氧化速率,监测反应过程中氧气浓度的变化。采用电子自旋共振光谱研究作用前后抗氧化剂对不同种类自由基的清除能力。结果:加入纳米金后,抗坏血酸及表儿茶素的氧化速率迅速提高,此过程伴随氧气的大量消耗。同时,与纳米金作用后的抗氧化剂清除自由基的能力显著降低。结论:纳米金颗粒能催化氧化不同种类的抗氧化剂,并显著抑制其抗氧化功能。

Objective:To investigate the effect of gold nanoparticles on the oxidation process and biological effect of ascorbic acidand epicatechin.Methods:Gold nanoparticles of about 5 nm were synthesized.By ultraviolet-visible spectroscopy,we studied theoxidation rate of the two antioxidants before and after the addition of gold particles,and monitored oxygen concentration changes inthe reaction process.Using electron spin resonance spectroscopy,we investigated the effect of clearance ability of antioxidants ondifferent types of free radical.Results:After adding gold nanoparticles,the oxidation rate of ascorbic acid and epicatechin wasrapidly increased,and the process was accompanied by a large amount of oxygen consumption.At the same time,the ability ofremoving free radicals was significantly decreased after the action of gold nanoparticles.Conclusion:Gold nanoparticles cancatalyze different types of antioxidants,and significantly inhibit the oxidation.