Baicalein, a kind of flavonoid, has many medical benefits, and therefore, its accurate and efficient determination is necessary in the field of medical ingredient detection. To achieve the rapid and precise detection of baicalein, a three-dimensional (3D) expansion–contraction wave micromixer was designed and used along with an electrochemical detection method to assemble a micromixing electrochemical detection system. First, the performances of the wave micromixers were investigated using the COMSOL Multiphysics 5.3 a software with three optimisation objectives, namely, the mixing uniformity, pressure drop, and mixing performance index, to comprehensively evaluate the properties of the micromixers. Second, a 3D expansion–contraction wave micromixer with optimal mixing properties was fabricated using the 3D printing technology. Third, a micromixing electrochemical detection system was built to study the redox behaviours of baicalein through the electrochemical cyclic voltammetry method. The effects of buffer varieties, buffer pH values, scanning speeds, and inlet flow rates on the redox curves of baicalein were studied to determine the appropriate experimental conditions. The results demonstrated that the currents of the oxidation peak increased linearly with the baicalein concentrations within the range of 3.55 10⁻⁶–5.92 10⁻⁵ mol l⁻¹ and the detection limit of 1.861 10⁻⁸ mol l⁻¹ (S/N = 3). The relative standard deviation among the results obtained through repeated experiments was 2.86%; this proves a high detection reproducibility of the new method. Compared with spectrophotometry, the error determined using the novel method in a real sample detection was 0.31%, thus achieving an efficient and precise detection of baicalein. The micromixing electrochemical detection method can remarkably improve the mixing efficiency, shorten the detection time, and decrease the detection limit, and therefore could be popularised for the exact content detection of other flavonoids.

黄ical素是一种类黄酮，具有许多医疗益处，因此，在医疗成分检测领域，准确而有效的测定是必要的。为了实现黄ical素的快速，精确检测，设计了三维（3D）膨胀/收缩波微混合器，并将其与电化学检测方法一起用于组装微混合电化学检测系统。首先，使用具有三个优化目标（即混合均匀性，压降和混合性能指标）的COMSOL Multiphysics 5.3软件研究波动微混合器的性能，以全面评估微混合器的性能。其次，使用3D打印技术制造了具有最佳混合特性的3D伸缩波微混合器。第三，建立了微混合电化学检测系统，通过电化学循环伏安法研究黄ical素的氧化还原行为。研究了缓冲液种类，缓冲液pH值，扫描速度和入口流速对黄ical素氧化还原曲线的影响，以确定合适的实验条件。结果表明，随着黄ical素浓度在3.55 10范围内，氧化峰电流线性增加。^-6 –5.92 10 ^-5 mol l ^-1和检测限为1.861 10 ^-8 mol l ^-1（S / N = 3）。通过重复实验获得的结果之间的相对标准偏差为2.86％；这证明了该新方法的高检测重现性。与分光光度法相比，在实际样品检测中使用新方法测定的误差为0.31％，从而实现了黄ical素的高效，精确检测。微混合电化学检测方法可显着提高混合效率，缩短检测时间，降低检测限，因此可推广用于其他类黄酮的准确含量检测。