Matrix-assisted ionization in vacuum (MAIV) was used to analyze the polyphenol content of ten different tea infusions. Nine different Camellia sinensis infusions were analyzed including three green teas, two black teas, two oolong teas, jasmine tea, and white tea. An infusion of rooibos (Aspalathus linearis) tea was also analyzed. Each freshly brewed tea was diluted 1:1 with methanol, and 100 ppm of phenolphthalein was added as an internal standard. An excess of 3-nitrobenzonitrile (NBN) was added to each vial, and the solution containing NBN crystals was analyzed by aspiration directly into the mass spectrometer sampling orifice. A working curve constructed for dilutions of catechin with phenolphthalein internal standard showed good linearity for five replicates of each concentration. The measured relative abundances of flavonoid polyphenols in each tea were in good agreement with previously reported values. Polyphenol content in tea infusions varied from 19.2 to 108.6 mg 100 mL⁻¹. In addition to the expected catechin flavonoids, abundant quinic acid and gallic acid was detected in the C. sinensis infusions. Characteristic A. linearis flavonoids were detected in the rooibos tea.

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真空中的基质辅助电离（MAIV）用于分析十种不同茶浸液中的多酚含量。分析了九种不同的山茶茶浸液，包括三种绿茶，两种黑茶，两种乌龙茶，茉莉花茶和白茶。如意宝（Aspalathus linearis）的注入）还对茶进行了分析。将每种新鲜冲泡的茶用甲醇按1：1比例稀释，然后添加100 ppm的酚酞作为内标。向每个小瓶中添加过量的3-硝基苯甲腈（NBN），然后直接将其抽吸至质谱仪采样孔中，对含有NBN晶体的溶​​液进行分析。用酚酞内标物稀释儿茶素所建立的工作曲线显示每个浓度重复五次时具有良好的线性。每种茶中黄酮类多酚的相对相对丰度与先前报道的值相吻合。茶浸液中的多酚含量从19.2到108.6 mg 100 mL ^-1不等。除了预期的儿茶素类黄酮以外，在中华茶树中还检测到丰富的奎尼酸和没食子酸输液。在如意宝茶中检测到特征性线虫黄酮。

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