Transcutaneous Drug Delivery Systems Based on Collagen/Polyurethane Composites Reinforced with Cellulose

Designing composites based on natural polymers has attracted attention for more than a decade due to the possibility to manufacture medical devices which are biocompatible with the human body. Herein, we present some biomaterials made up of collagen, polyurethane, and cellulose doped with lignin and lignin-metal complex, which served as transcutaneous drug delivery systems. Compared with base material, the compressive strength and the elastic modulus of biocomposites comprising lignin or lignin-metal complex were significantly enhanced; thus, the compressive strength increased from 61.37 to 186.5 kPa, while the elastic modulus increased from 0.828 to 1.928 MPa. The release of ketokonazole from the polymer matrix follows a Korsmeyer–Peppas type kinetics with a Fickian diffusion. All materials tested were shown to be active against pathogenic microorganisms. The mucoadhesiveness, bioadhesiveness, mechanical resistance, release kinetic, and antimicrobial activity make these biocomposites to be candidates as potential systems for controlled drug release.

Advancement of Lipid-Based Nanocarriers and Combination Application with Physical Penetration Technique

On account of the advantages of transdermal delivery and the application situation of transcutaneous technology in transdermal delivery, the article critically comments on nanosystems as permeation enhancement model. Nanosystems possess great potential for transcutaneous drug delivery. This review focuses on recent advances in lipid-based nanocarriers, including liposome, transfersomes, ethosomes, nanoemulsions, solid lipid nanoparticles, nanostructured lipid carriers and combination application of the lipid-based nanocarriers with microneedle, iontophoresis, electroporation and sonophoresis in the field for the development of the transdermal drug delivery system. We attempted to give an overview of lipid-based nanocarriers with the aim to improve transdermal and dermal drug delivery. A special focus is given to the nanocarrier composition, characteristic and interaction mechanisms through the skin. Recent combination applications of lipid-based nanocarriers with the physical penetration technology demonstrate the superiority of the combined use of nanocarriers and physical methods in drug penetration enhancement compared to their single use. In the future, lipidbased nanocarriers will play a greater role in the field of transdermal and dermal drug delivery.

Laser ablation-enhanced transdermal drug delivery

Transdermal delivery offers an excellent route for drug and vaccine administration. Nonetheless, the lipid-rich outer stratum corneum layer of the skin presents a critical challenge to drug penetration. Laser ablation perforates epidermis through selective photothermolysis, making skin more permeable to hydrophilic and macromolecular drugs such as peptides, proteins, and genes. This review summarizes recent applications to laser ablation-enhanced transdermal delivery. Needle- and pain-free transcutaneous drug delivery via laser ablation provides an alternative approach to achieve local or systemic therapeutics.