Dielectric Analysis of Phosphorylcholine Head Group Mobility in Egg Lecithin Liposomes

摘要: Purpose. A knowledge of the interfacial properties lecithin underpins our understanding many physicochemical characteristics drug delivery systems such as liposomes and stabilized microemulsions. In order to further this understanding, a high frequency dielectric study egg was undertaken. Methods. The effect temperature, concentration probe sonication on liposomal suspensions investigated by relaxation spectroscopy between 0.2-6 GHz. Results. dependent permittivity each suspension exhibited dispersion centred around 100 MHz, corresponding zwitterionic head groups. activation energy for group reorientation estimated Delta H = 6.3 kT mol(-1). There an increase in extent inter-head interactions increasing liposome volume fraction, whereas showed that: (i) groups both outer inner lamellae contribute response; (ii) may be less restricted surface curvature with few lamellae; (iii) increased sonication, result reduction amount (depolarized) interlamellar water following number per liposome. Conclusions, Dielectric analysis therefore provides means investigating liposomes, used investigate drugs other solutes membranes.