title: Fluidity enhancement: a critical factor for performance of liposomal transdermal drug delivery system.
abstract: Liposomes are well known lipid carriers for drug delivery of bioactive molecules encapsulated inside their membrane. Liposomes as skin drug delivery systems were initially promoted primarily for localized effects with minimal systemic delivery. Subsequently, a novel vesicular system, transferosomes was reported for transdermal delivery with efficiency similar to subcutaneous injection. The multiple bilayered organizations of lipids applied in these vesicles structure are somewhat similar to complex nature of stratum corneal intercellular lipids domains. The incorporation of novel agents into these lipid vesicles results in the loss of entrapped markers but it is similar to fluidization of stratum corneum lipids on treatment with a penetration enhancer. This approach generated the utility of penetration enhancers/fluidizing agents in lipids vesicular systems for skin delivery. For the transdermal and topical applications of liposomes, fluidity of bilayer lipid membrane is rate limiting which governs the permeation. This article critically reviews the relevance of using different types of vesicles as a model for skin in permeation enhancement studies. This study has also been designed to encompass all enhancement measurements and analytical tools for characterization of permeability in liposomal vesicular system.
authors.affiliation: Department of Pharmaceutical Sciences, Faculty of Ayurved & Medical Sciences, Gurukul Kangri University , Haridwar, Uttarakhand , India and.
authors.forename: Vipin Kumar
authors.initials: VK
authors.lastname: Sharma
authors.forename: Khomendra Kumar
authors.initials: KK
authors.lastname: Sarwa
authors.forename: Bhaskar
authors.initials: B
authors.lastname: Mazumder
mesh_terms: D000279:Administration, Cutaneous; D000818:Animals; D002152:Calorimetry, Differential Scanning; D004058:Diffusion; D016503:Drug Delivery Systems; D004548:Elasticity; D004578:Electron Spin Resonance Spectroscopy; D004817:Epidermis; D008081:Liposomes / Q000737:chemistry*; D008560:Membrane Fluidity / Q000187:drug effects; D008812:Mice, Hairless; D010539:Permeability; D010713:Phosphatidylcholines / Q000737:chemistry; D012869:Skin Absorption; D013501:Surface-Active Agents / Q000737:chemistry; D013816:Thermodynamics
chemical_list: D008081:Liposomes; D010713:Phosphatidylcholines; D013501:Surface-Active Agents
keywords: Flexibility; fluidizing agents; lipid bilayer; lipid vesicles