毛细管电泳-质谱联用法测定葡萄酒中8种有机酸含量

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

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(50μm×80cm)中,以40.0mmol/L醋酸铵(用1.0mol/L醋酸调至pH 4.5)为缓冲溶液,30%异丙醇(含3.0mmol/L氨水)为鞘液,分离电压25.0kV,各组分在15min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5.0～1 500.0mg/L;检出限分别为0.2、0.05、1.0、0.5、1.0、0.3、1.0、1.0mg/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。

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 sepa- rated 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-70G water mixture（containing 3 mol/L ammonia） as the sheath liquid. The baseline separation of eight compounds was achieved within 15 rain with satisfactory repeatability and sensitivity. The linear ranges are 1.0-0-300.0, 1.0 300.0, 5.0--1 500.0, 2.0--600.0, 5.00--1 500.0,1.0-0-300. 0, 5. malic, ascorbic, 0.3, 1.0, 1.0 87.6%--98.2% 0--1 500. 0 and 5.0--1 500.0 mg/L for oxalic, fumaric, succinic, citric, tartaric and tartaric acid with detection limits of 0.2, 0.05, 1.0, 0.5, 1.0, mg/L, respectively. The average recoveries of the eight components are with the RSDs of 2.7 %--5.6 %.