用聚乙二醇和低速离心机制备低密度脂蛋白

Preparation of low density lipoprotein by polyethylene glycol

目的探索用大容量低速离心机和廉价无毒的化学试剂规模化纯化低密度脂蛋白(LDL)的方法。方法以人血清为原料,加聚乙二醇6000(PEG6000)沉淀LDL,加NaCl调节液体密度并离心,反复此过程,逐步改变PEG6000和NaCl的浓度和配比直至LDL沉淀在离心后漂浮在液体表面从而与其他蛋白质分离。结果得到的LDL经鉴定纯度>95%,得率>50%。结论LDL因含脂质,在沉淀的状态下密度也较低,被置于较高密度的溶液中经低速离心,脂蛋白沉淀会漂浮在溶液表面,从而与其他蛋白分离。这是一个全新的脂蛋白分离方法,具有操作简便,处理容量大,试剂易得价廉且安全,器材要求低,得率较高,适用于各种实验室和生物制品厂,为LDL的各种研究提供了一个便利条件。用该法制备的高值品可用于生化检验中血脂测定的方法学验证和纯化相关载脂蛋白的起始物。本方法将为LDL药物化研究后的成果推广应用提供技术储备。

Objective To explore the method of large-scale purification of low density lipoprotein(LDL)u-sing a large capacity low-speed centrifuge and cheap non-toxic chemical reagents.Methods Using human ser-um as raw material,add PEG 6000 to precipitate LDL,add NaCl to adjust the liquid density and centrifuge,re-peat this process,gradually change the concentration and ratio of PEG 6000 and NaCl until the LDL precipitate floats on the liquid surface after centrifugation to separate from other proteins.Results The purity of LDL was more than 95%and the yield was more than 50%Conclusion Because LDL contains lipid,its density is also low in the state of precipitation.After being placed in a solution with higher density and centrifuged at low speed,lipoprotein precipitation will float on the surface of the solution,thus separating from other pro-teins.This is a new method for separating lipoproteins.It is simple to operate,has large processing capacity,is easy to get reagents,cheap and safe,requires low equipment,and has a high yield.It is suitable for various la-boratories and biological product factories,providing a convenient condition for various researches on LDL.The high-value product prepared by this method can be used for the methodological validation of blood lipid determination in biochemical tests and the purification of the starting material of related apolipoprotein.This method will provide technical reserves for the popularization and application of the results of LDL pharmaceu-tical research.