Determination of Total Antioxidant Capacity of Commercial Beverage Samples by Capillary Electrophoresis via Inline Reaction with 2,6-Dichlorophenolindophenol
Determination of Total Antioxidant Capacity of Commercial Beverage Samples by Capillary Electrophoresis via Inline Reaction with 2,6-Dichlorophenolindophenol
复制标题
DOI：
10.1021/jf901214r
复制
发表时间：
2009-08-12
影响因子：
6.1
通讯作者：
Strein, Timothy G.
中科院分区：
文献类型：
--
作者：
Merola, Emily T.;Catherman, Adam D.;Strein, Timothy G.
本文证明了使用的概念验证介导的微量分析（EMMA）作为一种新的方法来确定总抗氧化能力（TAC）。EMMA是一种低容量、高效率的毛细管电泳技术，迄今为止尚未充分用于小分子反应。在这里，纳升体积的2，6-二氯酚靛酚（DCIP）试剂溶液与含抗氧化剂的样品在窄孔毛细管的范围内混合。当在毛细管的长度上施加电压场时，通过利用试剂的不同迁移速率来实现混合。随后DCIP和抗氧化剂之间的电子转移反应用作样品TAC的定量测量。使用任一氧化还原形式的DCIP的线性校准用抗坏血酸的标准溶液完成。几个商业饮料样品进行了分析，并与广泛使用的铁还原抗氧化能力（FRAP）光谱法获得的结果与报告的方法获得的TAC值进行了比较。对于未知离子强度的真实的样品的分析，标准加入的方法被证明是上级使用外部校准。这种易于自动化的EMMA方法可能代表一种有用的新方法，以TAC测定。
This paper demonstrates proof-of-concept for the use of electrophoretically mediated microanalysis (EMMA) as a new approach to the determination of total antioxidant capacity (TAC). EMMA is a low-volume, high-efficiency capillary electrophoretic technique that has to date been underutilized for small molecule reactions. Here, nanoliter volumes of 2,6-dichlorophenolindophenol (DCIP) reagent solution are mixed with an antioxidant-containing sample within the confines of a narrow-bore capillary tube. The mixing is accomplished by exploiting differential migration rates of the reagents when a voltage field is applied across the length of the capillary tube. The ensuing electron transfer reaction between DCIP and the antioxidant(s) is then used as a quantitative measure of the TAC of the sample. Linear calibration using either redox form of DCIP is accomplished with standard solutions of ascorbic acid. Several commercial beverage samples are analyzed, and the TAC values obtained with the reported methodology are compared to results obtained with the widely used ferric reducing antioxidant power (FRAP) spectroscopic method. For the analysis of real samples of unknown ionic strength, the method of standard additions is shown to be superior to the use of external calibration. This easily automated EMMA method may represent a useful new approach to TAC determination.