劉得任D. Z. Liu; Y. L; Hsieh ; S. Y; Chang and W. Y; Chen2026-05-222026-05-222003https://203.71.86.71/handle/123456789/27801Liposomes were prepared from mixtures of egg-PC, cholesterols and distearoyl-phosphatidyl-ethanolamine covalently attached poly-ethylene glycol (PEG) with a molecular of weight 2000 (DSPE–PEG2000). In this work examines how PEG2000-grafted lipids affect the surface properties of the egg phosphatidylcholine (egg-PC) liposomal bilayer membrane through zeta potential and interaction potential measurements using microcalorimetry. Experimental results demonstrate that the absolute value of the zeta potential of PEG2000-grafted PC liposomes decreased from −19 to −8 mV when increasing DSPE–PEG2000 from 0 to 7 mol fraction, and the repulsive interaction potential of PEG2000-grafted PC liposomes decreased compared with those liposomes without PEG-grafting. However, the phenomenon of fusion between the liposomes incorporated with PEG-grafted PC was reduced. In brief, this result of fusion is contrary to the expectation of the interaction potential measurement; therefore, we believe that the steric hindrance of the grafted PEG2000 molecules on the liposomal surface contribute to a major imposition on the approach between liposomal surface and the formation of inverted micelles which are suggested as the necessary steps of liposome fusion.Liposomes were prepared from mixtures of egg-PC, cholesterols and distearoyl-phosphatidyl-ethanolamine covalently attached poly-ethylene glycol (PEG) with a molecular of weight 2000 (DSPE–PEG2000). In this work examines how PEG2000-grafted lipids affect the surface properties of the egg phosphatidylcholine (egg-PC) liposomal bilayer membrane through zeta potential and interaction potential measurements using microcalorimetry. Experimental results demonstrate that the absolute value of the zeta potential of PEG2000-grafted PC liposomes decreased from −19 to −8 mV when increasing DSPE–PEG2000 from 0 to 7 mol fraction, and the repulsive interaction potential of PEG2000-grafted PC liposomes decreased compared with those liposomes without PEG-grafting. However, the phenomenon of fusion between the liposomes incorporated with PEG-grafted PC was reduced. In brief, this result of fusion is contrary to the expectation of the interaction potential measurement; therefore, we believe that the steric hindrance of the grafted PEG2000 molecules on the liposomal surface contribute to a major imposition on the approach between liposomal surface and the formation of inverted micelles which are suggested as the necessary steps of liposome fusion.en-US生醫材料暨組織工程研究所期刊論文article