比较了以聚乙二醇和硫酸铵两种沉淀方法分离纯化腹水中单克隆抗体后，对不同亚类单克隆抗体活性的影响。结果表明，经３３％的硫酸铵沉淀腹水ＩｇＧ时，对其活性没有明显影响；沉淀ＩｇＭ时其活性明显降低。以聚乙二醇进行沉淀，对腹水单克隆抗体ＩｇＧ和ＩｇＭ活性均无明显影响，但依不同亚类的单克隆抗体，所选用的聚乙二醇浓度不同，对于ＩｇＧ，以１５％聚乙二醇沉淀较为合适，而沉淀ＩｇＭ时，则以６％聚乙二醇较为合适。 The effect of different monoclonal antibodies on the activity of different subclasses was compared after the monoclonal antibodies in ascites were separated and purified by two precipitation methods: polyethylene glycol and ammonium sulfate. The results showed that IgG was precipitated by 33% ammonium sulfate, but had no obvious effect on its activity. Precipitation with polyethylene glycol had no significant effect on the activity of ascitic monoclonal antibodies IgG and IgM, but with different subclasses of monoclonal antibodies, the concentrations of polyethylene glycol used were different, with IgG at 15% Diol precipitation is more appropriate, and precipitation of IgM, then 6% polyethylene glycol is more appropriate.