Faculty of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, 64023 Teramo, Italy.
Faculty of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, 64023 Teramo, Italy.
Food Chem. 2018 Aug 1;256:342-349. doi: 10.1016/j.foodchem.2018.02.141. Epub 2018 Feb 26.
A single-step, rapid (10 min), sensitive silver nanoparticles (AgNPs) based spectrophotometric method for antioxidant capacity (AOC) assay has been developed. The assay is based on the ability of natural polyphenols to reduce Ag(I) and stabilize the produced AgNPs(0) at room temperature. Localized surface plasmon resonance (LSPR) of AgNPs at ≈420 nm is then measured. Using different conditions of pH (8.4) and temperature (45 °C) a further assay based on the production of AgNPs with selectivity for flavonols was also developed. The reactivity of the two AgNPs based assays vs. 15 polyphenols belonging to different chemical classes and 9 different samples has been studied and compared with ABTS, Folin and AuNPs based methods for AOC. The proposed assays had good reproducibility (RSD ≤ 13) and are simple, sensitive and cost effective. Moreover, used in conjunction with the classical AOC assays, can improve the information on the polyphenolic pool of food samples.
一种基于银纳米粒子（AgNPs）的单步快速（10 分钟）分光光度法抗氧化能力（AOC）测定法已经建立。该测定法基于天然多酚还原 Ag(I) 和在室温下稳定生成的 AgNPs(0)的能力。然后测量 AgNPs 在 ≈420nm 处的局域表面等离子体共振（LSPR）。通过改变 pH（8.4）和温度（45°C）条件，还开发了一种基于选择性生成黄酮醇的 AgNPs 的进一步测定法。已经研究了两种基于 AgNPs 的测定法与属于不同化学类别的 15 种多酚和 9 种不同样品的反应性，并与 ABTS、Folin 和 AuNPs 基于 AOC 的方法进行了比较。所提出的测定法具有良好的重现性（RSD≤13），简单、灵敏且具有成本效益。此外，与经典的 AOC 测定法结合使用，可以提高对食品样品中多酚类物质的信息。
