毛细管电泳-质谱联用法测定葡萄酒中8种有机酸含量

应用毛细管电泳-电喷雾电离质谱(CE-ESI-MS)联用法同时测定葡萄酒中草酸，富马酸,琥珀酸，柠檬酸，苹果酸，抗坏血酸,酒石酸和乳酸8种主要有效成分的含量。在未涂层石英毛细管（50 μm×80 cm）中，以40.0 mmol/L醋酸铵（用1.0 mol/L醋酸调至pH 4.5）为缓冲溶液，30%异丙醇（含3.0 mmol/L氨水）为鞘液，分离电压25.0 kV，各组分在15 min内得到完全分离。草酸，富马酸,琥珀酸，柠檬酸，苹果酸，抗坏血酸,酒石酸和乳酸的线性范围分别为1.0~300.0、1.0~300.0、5.0~1 500.0、2.0~600.0、5.0~1 500.0、1.0~300.0、5.0~1 500.0和5.0~1 500.0 mg/L；检出限分别为0.2、0.05、1.0、0.5、1.0、0.3、1.0、1.0 mg/L；8种组分的加标回收率为87.6%~98.2%；相对标准偏差(RSD)在2.7%~5.6%之间。

Simultaneous Determination of Eight Organic Acids in Grape Wines by Capillary Electrophoresis-Electrospray Ionization Mass Spectrometry

A capillary electrophoresis-electrospray ionization mass spectrometry (CE-ESI-MS) method for the simultaneous determination of oxalic, fumaric, succinic, citric, malic, ascorbic, tartaric and tartaric acid in grape wines was established. The samples were separated by an uncoated capillary(50 μm×80 cm) on the operating voltage of 25 kV using 40.0 mmol/L ammonium acetate (pH 4.5) as the running buffer and 30% 2-propanol-70% water mixture(containing 3 mol/L ammonia) as the sheath liquid. The baseline separation of eight compounds was achieved within 15 min with satisfactory repeatability and sensitivity. The linear ranges are 1.0-300.0, 1.0-300.0, 5.0-1 500.0, 2.0-600.0, 5.0-1 500.0, 1.0-300.0, 5.0-1 500.0 and 5.0-1 500.0 mg/L for oxalic, fumaric, succinic, citric, malic, ascorbic, tartaric and tartaric acid with detection limits of 0.2, 0.05, 1.0, 0.5, 1.0, 0.3, 1.0, 1.0 mg/L, respectively. The average recoveries of the eight components are 87.6%-98.2% with the RSDs of 2.7%-5.6%.