不同电荷载溶菌酶脂质体的构建及其性质研究

The Preparation and Characterization of Differently Charged Lysozyme-Liposomes

采用改进的逆相蒸发法制备电中性、正电性和负电性溶菌酸脂质体，经Sepharose4B柱层析和高速离心纯化，结果表明脂质体酶具有潜在活性，即只有当脂质体被破坏时，酶活性才充分显露出来。带有不同种电荷的脂质体均能将正电荷溶菌酶包入其水相空间，负电荷脂质体对溶菌酶有更高的包封率。将脂质体酶与游离酶进行活性比较，前者具有缓释性。采用氯仿破膜能明显消除脂质和去垢剂对酶活测定（A540）的干扰。

Neutral, positively and negatively charged Lysozyme-Lipomes were made by modified reverse-phase evaporation method and purified with Scpharose 4B column chromatograpby and ultracentifugation. The results showed that the activity of lysozyme entrapped into lipemes was 'latent ', i. e. there is a little or no activity on subetrate unless the lipeomes were disrupted.Differently charged liposomes could capture positively charged lysozyme in the intersPace, which indicated that charge-induced associations were not necessary for enzyme capture. The negatively charged lipesome could capture the enzyme with higher entrapping efficiency. Comparing the activity of liposomal enzyme with that of free lysozyme under the same conditions, the former showed the slow-release characteristic. Using chloroform to disrupt the liposomes could remove the interferences of lipids and detergents obviously on the measurement of lysozyme's activity.