THOMAS LITHAA ,JOSE SHOMAA, GEORGE SACHIN JOHN A, VIDYA VISWANADA
Skin has become an impressive and idealistic platform for the delivery of drugs compared to other routes. However, the stratum corneum “dead, impermeable barrier devoid of biological activity” to skin had challenged the development of transdermal product, which delivers the drugs directly to the systemic circulation at a controlled rate[1]. Several approaches put forward to enhance the penetration of drug through skin for transdermal drug delivery and one among them are provesicular niosomes (proniosomes), which ideally possess the sole property of reversibly reducing the barrier resistance of the horny layer, allowing the drug to reach the living tissues at a greater rate. The provesicular niosomes (non-ionic surfactant based vesicles); colloid carrier is still in its infancy and need to exploit more in field of drug delivery. These vesicles are formed from the self-assembly of non-ionic amphiphiles in aqueous medium results in closed bilayer structure which can entraps both lipophilic and hydrophilic drugs[2]. They are non-toxic and non-immunogenic bilayer that be converted to niosomes when applied to skin by in-situ absorption of water and interacts with the strong hydrogen bond of stratum corneum and loosens it, thereby allowing the diffusion of drug into the skin. It also possesses enhanced stability compared to other vesicular carrier. This review is an insight into the exploitation of the various properties of drug to encapsulated, preparation, mechanism of penetration and application in transdermal drug delivery. The factor affecting the entrapment and penetration of drug through the skin also reviewed.
