1. Limitation of transdermal delivery system
Skin as a barrier to drug transport
Skin Barrier function is mainly due to the outermost few microns of skin namely Stratum Corneum, which is a unique biomembrane. This extremely thin membrane is the least permeable layer of the skin due to its remarkable composition of terminally differentiated keratinocytes (compressed keratin-filled corneocytes) anchored in the lipophilic matrix.
The lipids in this lipophilic matrix are responsible for many functions such as providing diffusion pathway from skin surface to SC. The lipophilic matrix (Figure 1.) is unique because of its content as it composes of ceramides, free fatty acids and cholesterol but are absent of phospholipids which is surprising as …show more content…
Some of which could be when the most convenient of drug intake methods (the oral route) is not feasible. Although IV could be used to avoid many of the problems such as gastrointestinal and hepatic metabolism, but because it is an invasive technique it is not really popular especially for chronic administration. Thus alternative strategies are of a lot of interest. The several distinct advantages of the transdermal drug delivery system is that the skin presents a relatively large and readily accessible surface area (1–2 m2) for absorption, which can be used to an advantage by application of a patch-like device to the skin surface, which is a non-invasive and thus a patient compliant procedure that allows continuous intervention. Cite Transdermal drug delivery system: An …show more content…
(A) Liquid-jet injections deliver drugs into intramuscular, subcutaneous, or intradermal regions. (B) Permeability-based methods of transdermal drug delivery: (i) delivery through hair follicles; (ii) tape-stripping removes the stratum corneum and facilitates drug absorption; (iii) thermal or radio frequency wave-mediated ablation of the stratum corneum creates micropores that enhance drug delivery; (iv) colloidal carriers, such as microemulsions and transfersomes, enhance the dermal absorption of topically applied drugs; (v) low-frequency ultrasound increases drug delivery by making the skin more permeable; (vi) chemical enhancers or peptides for drug delivery; (vii) electroporation of the stratum corneum enhances drug delivery into the epidermis; (viii) microneedles penetrate into the epidermis to deliver drugs. (C) Powder injection delivers dry drug powders into superficial skin layers (epidermis and superficial dermis). Source: Adapted from Mitragotri,
Skin as a barrier to drug transport
Skin Barrier function is mainly due to the outermost few microns of skin namely Stratum Corneum, which is a unique biomembrane. This extremely thin membrane is the least permeable layer of the skin due to its remarkable composition of terminally differentiated keratinocytes (compressed keratin-filled corneocytes) anchored in the lipophilic matrix.
The lipids in this lipophilic matrix are responsible for many functions such as providing diffusion pathway from skin surface to SC. The lipophilic matrix (Figure 1.) is unique because of its content as it composes of ceramides, free fatty acids and cholesterol but are absent of phospholipids which is surprising as …show more content…
Some of which could be when the most convenient of drug intake methods (the oral route) is not feasible. Although IV could be used to avoid many of the problems such as gastrointestinal and hepatic metabolism, but because it is an invasive technique it is not really popular especially for chronic administration. Thus alternative strategies are of a lot of interest. The several distinct advantages of the transdermal drug delivery system is that the skin presents a relatively large and readily accessible surface area (1–2 m2) for absorption, which can be used to an advantage by application of a patch-like device to the skin surface, which is a non-invasive and thus a patient compliant procedure that allows continuous intervention. Cite Transdermal drug delivery system: An …show more content…
(A) Liquid-jet injections deliver drugs into intramuscular, subcutaneous, or intradermal regions. (B) Permeability-based methods of transdermal drug delivery: (i) delivery through hair follicles; (ii) tape-stripping removes the stratum corneum and facilitates drug absorption; (iii) thermal or radio frequency wave-mediated ablation of the stratum corneum creates micropores that enhance drug delivery; (iv) colloidal carriers, such as microemulsions and transfersomes, enhance the dermal absorption of topically applied drugs; (v) low-frequency ultrasound increases drug delivery by making the skin more permeable; (vi) chemical enhancers or peptides for drug delivery; (vii) electroporation of the stratum corneum enhances drug delivery into the epidermis; (viii) microneedles penetrate into the epidermis to deliver drugs. (C) Powder injection delivers dry drug powders into superficial skin layers (epidermis and superficial dermis). Source: Adapted from Mitragotri,