Self-assembled liposome gel from liposome and cholesterol-end capped polyethylene glycol, was systematically investigated by rheological method, especially in the aspect of its recovery ability upon either mechanical deformation or temperature change. The liposome gel was found to have rheological behavior similar to that of Maxwell model. The dynamic shear modulus of the liposome gel was dependent on both the liposome concentration and the polymer concentration. At low liposome concentration range (5–20 mM), dynamic shear modulus decreased considerably with the liposome concentration, implying the decrease of effective cross-linking density inside gel network due to the addition of liposome. The liposome gel network had a fast, self-healing ability even after high deformation, and the injectability of the gel was confirmed by injection experiment in vitro. The liposome gel also exhibited temperature stimuli responsive behavior and thermo-reversibility. Dynamic light scattering studies proved that the particle size of liposome remained almost unchanged before and after the addition of the polymer.
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