**10. Stabilization of liposome**

Stability is that prescribed preparation should remain with required preestablished limits at predetermined time period. Chemical instability is physical not stability with leakage in loaded drug molecules from lipid bilayers, vesicles fusion with forming aggregation [94]. Physicochemical instability of liposome suspension like hydrolysis, aggregation, fusion and oxidation can be avoided by preparing proliposomes [95]. Liposomal stability will be increased when preparing efficient formulation using lyophillization or freeze drying to form powder liposomes which can be reconstituted upon usage. Selection of lipid composition, concentration of bilayers, buffers, antioxidant, chelating agents and cryo protectants play vital role in liposomes preparation. Buffer solutions having neutral pH decreases hydrolysis and antioxidant like sodium ascorbate will decrease oxidation in liposomal dispersion.

Oxygen potential is minimized with nitrogen gas purging to liposomal dispersion to obtain stable formulation [96]. Using antioxidants, buffers with neutral pH and lyo or cryo protectants in freeze drying also gives stable liposomal formulation.
