Abstract
Aggregation-disaggregation phenomena were observed with light microscopy as functions of the liposome dispersion temperature and the concentration of liposomes which were made of dipalmitoyl phosphatidylcholine in distilled water. Colonies formed by aggregation of the liposomes remaining below the pretransition temperature (about 34°C) disaggregated at the pretransition temperature within 2-10mg/ml of dipalmitoyl phosphatidylcholine upon heating. Within 15-30mg/ml, the colonies have disaggregated at the maintransition temperature (42°C). These phenomena were reversible with respect to temperature. Furthermore, the aggregation and fusion of liposomes have been observed using polyethylene glycols. The abilities for aggregation and fusion, which became stronger with increasing molecular weight or concentration of the polyethylene glycols, were qualitatively observed
