基于金纳米便携功能水凝胶的酪胺可视化监测

Visual Monitoring of Tyramine Based on Hydrogel with Portable Function of Au Nanoparticles

为建立生物胺(biogenic amines,BAs)实时监测的比色传感方法,以功能性水凝胶为基底,将β-D-半乳糖五乙酸酯(β-D-galactose pentaacetate,β-D-GP)作为还原剂前体和氯金酸一起负载于功能性水凝胶上,BAs能将β-D-GP水解为还原性β-D-半乳糖,β-D-半乳糖进一步将氯金酸中的金离子(Au^(3+))还原为金纳米粒子(Au nanoparticles,AuNPs),导致颜色从无色变为紫红色,使用智能手机的图像处理软件获得试验体系红/绿/蓝(red/green/blue,RGB)数据,水凝胶的G值用于量化BAs的测定。进一步用紫外分光光度法验证该方法的可行性,并建立可视化探针。该文以酪胺(tyramine,Tyr)为模型,RGB法和紫外分光光度法分别在酪胺浓度为2~200μg/mL和0.25~160μg/mL范围内呈现良好的线性相关性,相关系数R^(2)大于0.980,且显色体系稳定,应用于发酵食品中生物胺的测定,其加标回收率在96.0%~124.0%。

In this study,a colorimetric sensing method for real-time monitoring of biogenic amines(BAs)was established.With functional hydrogel as the base,β-D-galactose pentaacetate(β-D-GP)was used as the precursor of the reducing agent and loaded on the functional hydrogel together with chloroauric acid.BAs could hydrolyze β-D-GP to reducing β-D-galactose,and β-D-galactose could further reduce the gold ion(Au^(3+))in chlorauric acid to Au nanoparticles(AuNPs),resulting in a color change from colorless to purplish red.The image processing software of the smartphone was used to obtain red/green/blue(RGB)data of the test system,and the G value of the hydrogel was used to quantify the determination of BAs.The feasibility of this method was verified by ultraviolet spectrophotometry,and a visual probe was established.By using tyramine(Tyr)as the model,the RGB method and ultraviolet spectrophotometry showed a good linear correlation in the range of tyramine concentration of 2-200μg/mL and 0.25-160μg/mL,respectively,and the correlation coefficient R^(2) was greater than 0.980.The color system was stable,and it was applied to the determination of BAs in fermented food,with recovery efficiencies of 96.0%-124.0%.