Invasomes-Novel Vesicular Carriers for Transdermal Drug Delivery Systems

Abstract

Transdermal drug delivery refers to a means of delivering drugs through the surface of the skin for local or systemic treatment. The drug functions after absorption through the skin into the systemic circulation via capillary action at a certain rate. Use of traditional physical and chemical enhancers to improve the transdermal permeation rate by increasing drug solubility, diffusion coefficient and reservoir effect is not feasible owing to the toxic side effects of the overuse of chemical penetration enhancers. Designing of a drug in the vesicular system has brought a new life to the old pre-existing drug and thus has improved its therapeutic efficacy by controlling and sustaining the actions. Vesicular carriers are one of the recently invented carriers. Liposomes, niosomes, transfersomes, ethosomes and invasomes constitute the major part of these vesicles that have been sufficiently employed for the treatment of variety of topical skin diseases. Invasomes are novel liposomal vesicular systems that exhibit improved transdermal penetration compared to conventional liposomes and ethosomes. These vesicles contain phospholipids, ethanol and terpene in their structures; these components confer suitable transdermal penetration properties to the soft vesicles. The main advantages of these nanovesicles lie in their ability to increase the permeability of the drug into the skin, decrease absorption into the systemic circulation, thus, limiting the activity of various drugs within the skin layer, enhancing patient compliance and comfort. In this paper, several features of invasomes, including their structure, mechanism of penetration, preparation, characterization and potential advantages in dermal drug delivery are highlighted. Enhanced delivery of drugs through the skin and cellular membranes by means of an invasomal carrier opens numerous challenges and opportunities for research and future development of novel improved therapies.