Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Burapha University, Chon Buri 20131, Thailand.
Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Mahidol University, Bangkok 10400, Thailand.
Talanta. 2019 Jun 1;198:542-549. doi: 10.1016/j.talanta.2019.02.048. Epub 2019 Feb 11.
We report the first use of a paper-based device as a simple, low-cost and rapid detection platform for simultaneous determination of antioxidant activity and total phenolic content in food samples. Two antioxidant activity assays including 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonate) radical cation (ABTS) assay and cupric reducing antioxidant capacity (CUPRAC) assay and one total phenolic content assay, Folin Ciocaltue reagent (FC) assay were simultaneously employed as a proof-of-concept. The device composed of a central sample zone connected to four pretreatment zones and consecutive detection zones to accommodate all three assays and a sample blank measurement. The analysis was achieved by dropping the samples onto the sample zone to flow to the pretreatment and detection zones containing the stored reagents for each antioxidant assay making the color change that was measured using imageJ software. Assay optimization including key reagent concentrations, reaction time, and surface modification were carried out to obtain sensitive and wide linear rage analyses. Various antioxidant standards were then evaluated to determine the analytical features of the method. The paper-based assays were successfully applied to detect antioxidant activity and total phenolic content in 10 beverage samples with similar gallic acid equivalent (GAE) values to those obtained from traditional assays at a 95% confidence interval. Moreover, the GAE values of the samples obtained from three assay analyses were well correlated to each other with relatively high Pearson's correlation coefficients. These results indicated that the assays gave accurate results and are suitable for simultaneous analysis of antioxidant activity and total phenolic content in real samples.
我们首次报道了一种基于纸张的设备，可作为一种简单、低成本且快速的检测平台，用于同时测定食品样品中的抗氧化活性和总酚含量。我们同时采用了两种抗氧化活性测定法，包括 2,2'-连氮基-双(3-乙基苯并噻唑啉-6-磺酸)自由基阳离子（ABTS）法和铜还原抗氧化能力（CUPRAC）法，以及一种总酚含量测定法，福林-希奥考尔特试剂（FC）法，以此作为概念验证。该设备由一个中央样品区连接到四个预处理区和连续的检测区组成，可容纳所有三种测定法和一个样品空白测量。通过将样品滴到样品区，使样品流到预处理和检测区，其中包含每种抗氧化测定法的储存试剂，以实现颜色变化，然后使用 ImageJ 软件进行测量。我们进行了测定法优化，包括关键试剂浓度、反应时间和表面修饰，以获得灵敏且宽线性范围的分析。然后，我们用各种抗氧化标准品来评估方法的分析特性。基于纸张的测定法成功地应用于 10 种饮料样品中抗氧化活性和总酚含量的测定，其测定结果与传统测定法的没食子酸当量（GAE）值在 95%置信区间内相似。此外，三种测定分析获得的样品的 GAE 值彼此之间具有良好的相关性，具有相对较高的皮尔逊相关系数。这些结果表明，这些测定法能够提供准确的结果，适用于实际样品中抗氧化活性和总酚含量的同时分析。
