衍生化-毛细管气相色谱法定量分析白念珠菌中甾醇含量

Determination of Sterols in Candida albicans by Derivation - Capillary Gas Chromatography

目的:建立衍生化-毛细管气相色谱法测定白念珠菌中羊毛甾醇和麦角甾醇等甾醇的含量。方法:白念珠菌经破碎、离心、皂化、提取出甾醇部分后再经1-三甲基甲硅烷咪唑(TMSI)硅烷化后,其TMSI衍生物采用HP 50毛细管柱进行气相色谱分析,柱温:程序升温150～290℃,起始温度150℃,按15℃·min^(-1)升至290℃恒定;检测器温度280℃;进样口温度270℃。柱头压35kPa;载气:氮气,流速82mL·min^(-1);每次进样量:1μL;分流比为100:1。结果:在0.1862～1.862mg·mL^(-1)衍生物的氯仿溶液范围羊毛甾醇和麦角甾醇线性关系良好(r分别为0.9996和 0.9969),回收率分别大于97％和93％(RSD<5％),最低检测限分别为1.86ng·mL^(-1)和2.54ng·mL^(-1),日内精密度良好(RSD均在5％以内)。结论:本方法准确、灵敏、专属性强,结果可靠,为抗真菌药物研究提供了有力的工具。

Objective: To establish a method of derivation - capillary gas chromatography for the determination of sterols in Candida albicans, such as lanosterol and ergosterol. Methods: The sterols extracted from Candida albi-cans were trimethylsilylated with TMSI and analyzed by gas chromatography with a HP 50 capillary column, tem-perature from 150℃ to 290℃ , 15℃ · min-1 ; detecter temperature 280℃ ; injection temperature 270℃; Head pressure 35 kPa; carrier gas is nitrogen, flow rate 82 mL · min-1 ; splic ratio 100: 1. Results: Chloroform solutions of deviated sterols range from 0. 186 2 - 1. 862 mg · mL-1 , linear relation of lanosterol and ergosterol were good (r =0. 999 6 and 0. 996 9 respective) . The average recoveries were more than 97% and 93% , RSD < 5% . The lowest detection limit were 1. 86 ng · mL-1 and 2. 54 ng · mL-1 respectively, the precision within day were good (RSD <5% ). Conclusion: This method is accurate, sensitive and specific. The results were relia-ble. It provides a powerful tool for the study of antifungal agents.