基于CoFe_(2)O_(4)介孔磁性纳米材料的单宁酸比色传感检测

Tannic Acid Colorimetric Detection Based on CoFe_(2)O_(4) Mesoporous Magnetic Nanoparticles

利用铁酸钴介孔磁性纳米材料(CoFe_(2)O_(4) mesoporous magnetic nanoparticles, CoFe_(2)O_(4)MMNPs)催化H_(2)O_(2)产生自由基,使得过氧化物酶的底物2,2-联氮-二(3-乙基-苯并噻唑-6-磺酸)二铵盐(2,2’-azino-bis(3-ethylbenzo-thiazoline-6-sulfonic acid) diammonium salt, ABTS)产生绿色的颜色反应。结合单宁酸会抑制CoFe_(2)O_(4)MMNPs的催化活性这一性质,建立一种可视化、快速、方便、灵敏的单宁酸检测方法。通过对实验条件的优化,得出单宁酸摩尔浓度与该体系在415 nm处的吸光度具有良好的线性关系,其线性范围为1.0×10^(-7)~5.0×10^(-6) mol/L,检测限为5.0×10^(-8) mol/L。此外,考察了一定摩尔浓度单宁酸类似物的干扰情况,其结果表明该传感器具有很好的选择性。该研究有望应用于食品中单宁酸的检测。

We use the catalytic activity of CoFe_(2)O_(4) mesoporous magnetic nanoparticles(CoFe_(2)O_(4) MMNPs)for the oxidation of a peroxidase substrate,2,2’-azino-bis(3-ethylbenzo-thiazoline-6-sulfonic acid)diammonium salt(ABTS)by H_(2)O_(2) into a colored oxidation product,and the property that tannic acid can scavenge the catalytic activity of CoFe_(2)O_(4) MMNPs to establish a quick,convenient and sensitive colorimetric determination of tannic acid.By optimizing the experimental conditions,there is a good linear relationship between the absorbance at 415 nm and the concentration of tannin in the range from 1.0×10^(-7) to 5.0×10^(-6) mol/L,with the detection limit of 5.0×10^(-8) mol/L.In addition,the interference of tannic acid analogues with a certain concentration is investigated,and the results show that the sensor has good selectivity.This research is expected to be applied to the detection of tannic acid in food.