银杏酸的反相银化高效液相色谱法分离和测定

目的　建立银杏酸的反相银化高效液相色谱分离和含量测定方法。方法　用LC ESI MS对银杏叶中银杏酸进行鉴定,并用反相银化HPLC研究4种银杏酸的分离和含量测定。在银杏叶的乙醇浸提液中加入酸性盐溶液和少量吸附剂后,用正己烷萃取,N₂ 浓缩后的残留物进行HPLC分析。流动相为甲醇-5 %乙酸(90∶10 ) ,其中银离子浓度为0.03mol·L^-1 ,HPLC和二极管阵列检测联用对银杏酸色谱峰进行光谱分析和纯度鉴定。结果　反相银化HPLC分析银杏酸所确定的色谱峰是正确的,4种银杏酸与杂质成分均完全分离。平均回收率97.3% ,方法的精密度RSD为1.6 %。结论　反相银化HPLC是分离碳数与饱和度均不相同的同系物的有效方法,可用于银杏酸的定量分析和银杏叶生产的质量控制

SEPARATION AND QUANTITATIVE ANALYSIS OF GINKGOLIC ACIDS FROM GINKGO BILOBA LEAVES BY REVERSE PHASE ARGENTATION HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

AIM: To develop a reverse phase argentation high performance liquid chromatographic (RP-AHPLC) method for the separation and determination of ginkgolic acids. METHODS: Liquid chromatography-electrospray ionization mass spectrometry (LC/ESI-MS) was applied to identify ginkgolic acids from Ginkgo biloba leaves and four ginkgolic acids of the samples were separated and quantified by RP-AHPLC. Leaves were extracted with ethanol and analytes were extracted with hexane after addition of acid/salt solution and adsorbent to matrix solution. Ginkgolic acids were separated and determined within 30 minutes by RP-AHPLC under optimum chromatographic conditions. Methanol and 5% aqueous acetic acid (90:10) containing 0.03 mol.L-1 silver ion was used as mobile phase, column temperature was selected at 30 degrees C, flow rate was 1.0 mL.min-1, UV detection wavelength was at 310 nm. The spectra analysis and purity identification of chromatographic peaks of ginkgolic acids were further confirmed by means of diode array detection. RESULTS: Four ginkgolic acids were baseline separated from each other and from other interfering components. The average recovery and relative standard deviation of the method were 97.3% and 1.6%, respectively. CONCLUSION: RP-AHPLC was an excellent method for separation of homologous with different carbon atom numbers and double bond. The method is useful for the quality control of extract of Ginkgo biloba leaves.