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.
Bibliographical noteFunding Information:
This work was supported by the National First-Class Discipline of Food Science and Engineering Construction Project (JUFSTR20180205), the Independent Research Project of Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment and Technology (FMZ-202016), and the Postgraduate Research and Practice Innovation Program of Jiangsu Province (SJCX20-0758). The authors also wish to thank Professor Yu Liu for his technical support on the fabrication of micromixers.
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- Cyclic voltammetry
- Three-dimensional micromixer
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Mechanics of Materials
- Mechanical Engineering
- Electrical and Electronic Engineering