测定鸡蛋胆固醇的高效液相色谱新方法

An Improved Method of Cholesterol Determination in Egg Yolk by High Performance Liquid Chromatography

报道了测定鸡蛋蛋黄胆固醇含量的一种改进方法。蛋黄以水稀释后直接以乙醚和石油醚萃取，采用ＺｏｒｂａｘＯＤＳ反相色谱柱（０．４６ｃｍ×１５ｃｍ，５～６μｍ），以乙腈－异丙醇（４∶１，Ｖ／Ｖ）为流动相，流速０．６ｍＬ／ｍｉｎ，检测波长２０８ｎｍ。在此色谱条件下，胆固醇含量与色谱峰高呈良好的线性关系，线性范围在０．０５～０．４０ｇ／Ｌ（ｒ＝０．９９９３）之间，最小检测量为０．０２ｇ／Ｌ。用于蛋黄胆固醇分析，样品无须皂化便可直接定量，简便、快速、重现性好。

An improved method for cholesterol determination in egg yolk is reported in this paper. Egg yolk was first diluted. Cholesterol was then extracted with ethyl ether and petroleum ether, and quantified by reversed phase liquid chromatography on a Zorbax ODS column (0.46mm×15cm, 5.6μm) using a mobile phase of acetonitrile and 2 propanol (4∶1) with a flow rate of 0.6mL/min. A linear correlation was observed between 0.05 0.40 g/L of cholesterol. The determination limit was 0.02g/L. This proposed method of HPLC determination of egg yolk without saponification is superior to colorimetric determination on the sample with saponification, and comparable to HPLC determination with saponification of the egg yolk sample in terms of reliability. No difference in final results was observed between egg yolk sample with saponification and the same sample without saponification. Rapid and reproducible quantification of cholesterol in egg yolk can be completed with this new method. Omission of saponification has made this proposed method more convenient than those ever reported, and can be used in yolk cholesterol study with greater ease.