This paper describes the development of a novel electrochemical assay for the measurement of water-soluble vitamins in food and pharmaceutical products. The optimum conditions for the determination of vitamin B₁ (thiamine), B₂ (riboflavin) and B₆ (pyridoxine) in phosphate buffer were established using cyclic voltammetry in conjunction with screen printed carbon electrodes (SPCEs). The optimum current response for all three vitamins was achieved in 0.1 M phosphate buffer pH 11 using an initial potential of −1.0 V. Using square wave voltammetry, the linear ranges for thiamine, riboflavin, and pyridoxine were found to be: 15–110 µg/ml, 0.1–20 µg/ml, and 2–80 µg/ml respectively. The application of the method to a commercial food product yielded a recovery of 95.78% for riboflavin, with a coefficient of variation (CV) of 3.38% (n = 5). The method was also applied to a multi-vitamin supplement for the simultaneous determination of thiamine, riboflavin and pyridoxine. In both cases only simple dilution with buffer followed by centrifugation was required prior to analysis. The resulting square wave voltammetric signals were completely resolved with Ep values of −0.7 V, +0.2 V, and +0.6 V respectively. The recoveries determined for the vitamin B complex in a commercial supplement product were found to be 110%, 114%, and 112% respectively (CV = 7.14%, 6.28%. 5.66% respectively, n = 5).

本文介绍了一种用于测量食品和药品中水溶性维生素的新型电化学方法的开发。测定维生素B ₁（硫胺素）、B ₂（核黄素）和B _{6的最佳条件}使用循环伏安法结合丝网印刷碳电极 (SPCE) 建立磷酸盐缓冲液中的 (吡哆醇)。所有三种维生素的最佳电流响应均在 0.1 M 磷酸盐缓冲液 pH 11 中使用 -1.0 V 的初始电位实现。使用方波伏安法，发现硫胺素、核黄素和吡哆醇的线性范围为：15–110 µg /ml、0.1–20 µg/ml 和 2–80 µg/ml。将该方法应用于商业食品，核黄素的回收率为 95.78%，变异系数 (CV) 为 3.38% (n = 5)。该方法也适用于同时测定硫胺素、核黄素和吡哆醇的复合维生素补充剂。在这两种情况下，分析前只需要用缓冲液简单稀释，然后离心。得到的方波伏安信号完全解析，Ep 值分别为 -0.7 V、+0.2 V 和 +0.6 V。发现商业补充剂产品中维生素 B 复合物的回收率分别为 110%、114% 和 112%（CV 分别为 7.14%、6.28%、5.66%，n = 5）。