基于CeO_(2)/CoOOH纳米酶的比色分析法快速检测水果中抗坏血酸

Colorimetric Method Based on CeO_(2)/CoOOH Nanozyme for Rapid Detection of Ascorbic Acid in Fruits

本研究采用液相沉淀法合成了一种二氧化铈(CeO_(2))修饰羟基氧化钴(CoOOH)的纳米材料CeO_(2)/CoOOH。CeO_(2)/CoOOH具有良好的类氧化酶活性,可以直接氧化3,3',5,5'-四甲基联苯胺(3,3',5,5'-tetramethylbenzidine,TMB)为蓝色的氧化态-TMB (ox-TMB),而抗坏血酸(ascorbic acid,AA)的强还原性可以将ox-TMB还原为TMB,导致ox-TMB在652 nm波长处的吸光度降低,同时蓝色褪去。在此基础上开发了一种新的检测AA的比色传感器。结果表明:该传感器显示出对AA的高灵敏度响应性,检测限为2.73μg/mL,检测范围为5~100μg/mL,可成功应用于橙子和苹果样品中AA的快速检测。

In this study,cerium dioxide-modified cobalt oxyhydroxide(CeO_(2)/CoOOH)nanomaterial was synthesized by a liquid-phase precipitation method.CeO_(2)/CoOOH showed good oxidase-like activity toward 3,3’,5,5’-tetramethylbenzidine(TMB),and could directly oxidize TMB to ox-TMB,which presented a clear blue color.Reversely,ascorbic acid(AA)could reduce ox-TMB to TMB,leading to a decrease in the absorbance of ox-TMB at 652 nm and a fading of the blue color.Based on this phenomenon,a new colorimetric sensor for AA detection was developed.The sensor exhibited a highly sensitive response to AA with a limit of detection(LOD)of 2.73μg/mL and a wide detection range of 5-100μg/mL and could be successfully applied for rapid detection of AA in oranges and apples.