对鸡卵黄免疫球蛋白（IgY）的分离纯化进行了研究。工艺流程为：卵黄8倍水稀释并搅拌10 min用HCl调pH至5.2后在4 ℃静置2 h去沉淀在上清夜中加入95%冰乙醇（-20 ℃）使终浓度为60%（v/v）4 ℃搅拌20 min后离心（22000 r/min，4 ℃，25 min）收集沉淀并加入0.028 mol/L NaCl溶液在4 ℃下过滤除去脂蛋白沉淀收集的滤液用SDS-PAGE法进行纯化得纯度为98%的lgY。用大肠杆菌（E.coli）对其活性进行测定，效果良好，此方法能保持免疫球蛋白的活性。

The separation and purification of Immunoglobulin of egg yolk (IgY) were studied. The mixture of yolk and water (1:8, v/v) was stirred for 10 min and then its pH value was adjusted to 5.2 with HCl. After placing the mixture for 2 h at 4 ℃, the supernatant was diluted with 95% ice ethanol (-20 ℃) until its concentration reached 60% (v/v). Then the solution was stirred for 20 min at 4 ℃ and centrifuged (22000 r/min) for 25 min at 4 ℃. The precipitate was collected and added into 0.028 mol/L NaCl solution. The corresponding suspension was filtered at 4 ℃ to remove the lipoprotein sediment and the filtrate was then purified by SDS-PAGE methods, giving the protein IgY with the purify of 98%. Its activity was determined with Escherichia coli (E.coli) and results showed that this purification method could well maintain the activity of IgY.