功能化纳米金修饰电极检测食品中H2O2的残留量

通过电沉积法修饰功能化纳米金修饰电极,实现过氧化氢的电化学检测。通过研究修饰电极在过氧化氢中的电化学行为,得到检测过氧化氢的较优条件并建立检测过氧化氢标准曲线。得到优化条件为:功能化物质半胱氨酸/巯基乙胺、纳米金粒径15 nm、功能化物质浓度0.05 mol/L、扫描速度110 mV/s、检测过氧化氢时缓冲溶液pH为6.0等。过氧化氢标准曲线线性关系良好,相关系数r为0.997,检出限为0.129 μmol/L,定量限为0.431 μmol/L,具有良好的重现性和稳定性,精密度高,对葡萄糖、甘氨酸、抗坏血酸、钾盐、钠盐等具有较强的抗干扰能力,该修饰电极检测过氧化氢性能良好,在实际样品检测中回收率为92.1%~95.6%,RSD在2.26%~4.52%,可用于实际样品中过氧化氢的测定。

Determination of H2O2 Residue in Food by Functionalized Gold Nanomodified Electrode

The electrochemical detection of hydrogen peroxide was realized by electrodeposition of functionalized gold nanoparticles modified electrode. By studying the electrochemical behavior of self-assembled electrode in hydrogen peroxide,the better conditions for the detection of hydrogen peroxide were obtained and the standard curve for the detection of hydrogen peroxide was established. The optimized conditions were as follows:Cysteine/Mercapto ethylamine,particle size of gold nanoparticle 15 nm,concentration 0.05 mol/L,scanning speed 110 mV/s,pH6.0 when detecting hydrogen peroxide,etc.. The correlation coefficient r was 0.997,the detection limit was 0.129 μmol/L,and the quantitative limit was 0.431 μmol/L,with good reproducibility and stability,high precision,and strong anti-interference ability to glucose,glycine,ascorbic acid,potassium salt,sodium salt,etc.. The modified electrode had good performance in the detection of hydrogen peroxide. In the actual sample detection,the recovery was 92.1%~95.6%,RSD was 2.26%~4.52%,which could be used for the determination of hydrogen peroxide in the actual sample.