Chindaphan Kanokporn, Thaveesangsakulthai Isaya, Naranaruemol Suchapa, Nhujak Thumnoon, Panchompoo Janjira, Chailapakul Orawon, Kulsing Chadin
Department of Chemistry, Faculty of Science, Chulalongkorn University Bangkok 10330 Thailand
Chromatographic Separation and Flavor Chemistry Research Unit and Center of Molecular Sensory Science, Department of Chemistry, Faculty of Science, Chulalongkorn University Bangkok 10330 Thailand.
RSC Adv. 2021 Feb 2;11(11):5885-5893. doi: 10.1039/d0ra09089a.
Electrocoagulation (EC) approach was developed to allow fast sample cleanup step prior to selective analysis of non- and mono-hydroxylated phenolic acids in red wine samples with high performance liquid chromatography hyphenated with UV detection (HPLC-UV). EC system with the wine in KCl electrolyte (1.5 mol L) was employed removing the polymeric pigments with good recovery of 39 peaks from 64 peaks. The mechanisms mainly involve enrichment induced aggregation and reduction of the pigments at the cathode and the adsorption onto the EC sludge. The EC was further miniaturized employing two intercalated stainless steel spring electrodes at 9.0 V which allowed removal of >99% interference peak area from the pigments within 5 s. The recoveries of the target phenolic acids (-hydroxybenzoic acid, vanillic acid, syringic acid and ferulic acid) were within the range of 86-102%. The repeated analysis of these standards revealed <2 and ≤10% RSD of the intra-day and inter-day precisions, respectively. The linearities of their calibration curves were observed with > 0.99. Their method detection limits were within the range of 0.02-0.20 mg L.
开发了电凝法（EC），以便在采用高效液相色谱-紫外检测联用技术（HPLC-UV）对红酒样品中的非羟基和单羟基酚酸进行选择性分析之前，实现快速的样品净化步骤。采用在KCl电解质（1.5 mol/L）中的红酒的EC系统，去除聚合色素，从64个峰中回收了39个峰，回收率良好。其机制主要包括在阴极处富集诱导的聚集和色素还原以及对EC污泥的吸附。使用两个插入的不锈钢弹簧电极在9.0 V下进一步将EC小型化，这使得在5秒内从色素中去除>99%的干扰峰面积。目标酚酸（对羟基苯甲酸、香草酸、丁香酸和阿魏酸）的回收率在86-102%范围内。对这些标准品的重复分析显示，日内精密度和日间精密度的相对标准偏差分别<2%和≤10%。观察到它们校准曲线的线性，相关系数>0.99。它们的方法检测限在0.02-0.20 mg/L范围内。
