Preparation and Characteristics of Unsaturated PE Immunoliposome Incorporated with Ganglioside $G_{M1}$

Ganglioside $G_{M1}$을 함유한 불포화 PE Immunoliposome의 제조와 특성

The storage stabilities of immunoliposomes incorporated with variable amounts of ganglioside $G_{M1}$ were investigated as a function of time. temperature. and composition by observing absorbance of visible light and calcein release. In the column chromatographe, the layer of unsaturated PE(dioleoylphosphatidylethanolamine : DOPE). unable to form stable liposomes at physiological temperature and pH, were formed when palmitoyl-immunoglobulin G(IgG) $(2.5{\times}10^{-4}\;mol/DOPE\;mol)$ added. The incorporation of ganglioside $G_{M1}$ into immunoliposome. enhanced the stabilities of bilayers during the extended period of storage. The turbidities of immunoliposomes coated with ganglioside $G_{M1}$ exhibited the maximum near 20 mol% $G_{M1}/DOPE$ mol. probably because of the disturbance of the bilayer characteristics, i.e., layer transition or reorientation of interaction sites. At low temperature. the higher stability was achieved than at elevated temperatures. After one week of storage. the redispersed liposomal solutions at lower temperatures maintained the original elution patterns in chromatography but broader distribution at elevated temperatures. During the storage, it is suggested the aggregation is the more dominant phenomena for liposomes kept at $5^{\circ}C$ than the fusion. while he fusion is at elevated temperatures.