江苏大学化学化工学院王坤教授团队在Food Chemistry发表题目为“Construction of a novel Au@Os mediated TMB-H2O2 platform with dual-signal output for rapid and accurate detection of ziram in food”研究论文（构建新型 Au@Os 介导双信号输出 TMB-H2O2 平台用于食品中福美锌的快速准确检测）。摘要： 3,3′,5,5′-四甲基联苯胺-H2O2 (TMB-H2O2) 平台已广泛用于快速检测食品中的各种分析物。然而，现有的 TMB-H2O2 平台的准确性有限，因为它们的信号输出仅限于可见光区域，而这很容易受到实际样品中各种食品着色剂的干扰。为了应对这一挑战，我们开发了一种新型 Au@Os 介导的 TMB-H2O2 平台，用于快速准确地检测食品中的分析物。制备的 Au@Os NPs 表现出显著的过氧化物酶样活性，使该平台分别在可见光和近红外 (NIR) 区域显示双吸收峰。该 Au@Os 介导的 TMB-H2O2 平台对不同浓度的福美锌呈现三个线性范围，分别为 1–100、150–600 和 800–2000 nM，检测限 (LOD) 为 7.9 nM，定量限 (LOQ) 为 24.15 nM。此外，Au@Os 介导的 TMB-H2O2 平台还用于快速准确地检测苹果、番茄和红茶等真实食品样品中的福美锌。研究结果：3.1 Au@Os NPs 的合成Scheme 1. (a) Preparation of Au@Os NPs, (b) Mechanism involving the Au@Os NPs-mediated dual colorimetric system.Fig. 1. (A, D, G) UV–visible, TEM and XPS analysis of Au NPs, (B, E, H) UV–visible, TEM and XPS analysis of Os NPs, (C, F, I) UV–visible, TEM of Au@Os NPs and XPS analysis of Au@Os NPs.3.2 Au@Os核壳纳米粒子的开发阶段Fig. 2. Comparative study of UV–vis spectrum of Au@Os NPs with tuning the ratio of Os: Au1:Os1 (black line), Au1:Os2 (red line) and Au1:Os4 (blue line)3.3 Au@Os NPs介导的TMB-H2O2比色体系过氧化物酶特性研究Fig. 3. (A) UV–vis -NIR spectra of bare TMB, H2O2 and comparative study of different reaction systems-mediated by TMB- H2O2 colorimetric reaction systems (B) ESR spectra of cTMB and Au@Os-cTMB, inset shows the amplify spectra of cTMB, (C) comparative study at 652 nm of TMB+ H2O2 (blank) and TMB + H2O2 reaction system catalyzed by different NPs, (D) comparative study at 892 nm of TMB + H2O2 (blank) and TMB + H2O2 reaction system catalyzed by different NPs.3.5 实验条件优化Fig. 4. Effects of different experimental parameters; concentration of Au@Os NPs (A), concentration of H2O2 (B), concentration of TMB (C), pH (D), time (E) and temperature (F) on the absorbance of Au@Os NPs + TMB + H2O2 system incubated with DTCs at ΔA652 nm and ΔA892 nm.3.7 利用 au@Os NPs 检测福美锌Fig. 5. (a) UV–visible absorption spectra of H2O2 + TMB + Au@Os NPs by adding different concentrations of ziram (0, 1, 5, 10, 15, 20, 30, 40, 50, 60, 70, 80, 90, 100, 150, 200, 250, 300, 350, 400, 450, 500, 600, 800, 1000, 1500, and 2000 nM). (b) Representative photos of Au@Os NPs after incubation with different concentrations of ziram (c) The linear relationships between ∆A652 nm and various concentrations of ziram.Fig. 6. (a) Visible-NIR spectra of H2O2 + TMB + Au@Os NPs by adding different concentrations of ziram (0, 1, 5, 10, 15, 20, 30, 40, 50, 60, 70, 80, 90, 100, 150, 200, 250, 300, 350, 400, 450, 500, 600, 800, 1000, 1500, and 2000 nM). (b) The corresponding linear calibration curves after incubation with different concentrations of ziram.3.8 纳米酶的选择性Fig. 7. (a, b) The specificity and selectivity test of Au@Os nanozyme for detection of ziram at 652 nm and 892 nm. The concentrations of ziram were used 2000 nM, and the concentrations of the other metals cations and pesticides were 10 μM (c) typical photographs of various pesticides and metal cations after incubation with ziram.原文链接：https://doi.org/10.1016/j.foodchem.2024.140988
