Transdermal Delivery from LLC

We will focus on lyotropic hexagonal and cubic and their nano-dispersions as topical delivery vehicles. Recent advances in transdermal and mucosal dmg delivery via LLC carriers are demonstrated and discussed. 

Owing to the SC composition, its lipid phase behavior is different from that of other biological membranes. The hydrocarbon chains are arranged into regions of crystalline, lamellar gel, and lamellar LC phases, thereby creating various domains within the lipid bilayers [84]. Intrinsic and extrinsic proteins, such as enzymes, may also affect the lamellar stmcture of the SC. Water is a vital component of the structure, acting as a plasticizer to prevent cracking of the SC. 

Currently, various technologies are used to increase the permeability of macromolecules by exploring iontophoresis, electroporation, ultrasound, and micro-poration using electrical current/voltage, radio frequency, and microneedles to open the skin. Although mechanical abrasion and chemical enhancers may increase drag permeation, their effects on the skin s inherent rate-controlling properties are difficult to control and they may irritate the skin [85]. 

The limitations and the diflhculty in crossing the barrier of the SC by various molecules can be addressed and partially overcome via the skin application of penetration enhancers, compounds that increase the diffusion coefficient of the drug through the SC. 

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