Pharmaceutics & Novel Drug Delivery Systems

Biography

Biography: Fiorenza Rancan

Abstract

Despite skin accessibility, delivery of drugs across skin barrier and the maintenance of a constant drug concentration in the target region is still a challenge. Nanocarrier-based approaches have been shown to improve both dermal and transdermal drug delivery. Depending on the type of nanocarrier, different drug release properties as well as different interactions with skin barriers and cell components can be achieved. A systematic correlation between nanocarrier physicochemical characteristics and their skin penetration and drug delivery properties is necessary to foster the use of nanotechnology in dermatology. Nanocarriers physicochemical properties and their performance after application on human skin explants have been investigated by methods like atomic force microscopy and stimulated Raman spectroscopy, whereas fluorescence and electron microscopy as well as flow cytometry of single skin cells served to elucidate nanocarrier penetration pathway and cellular uptake. Results show that size, surface charge, type of cargo, softness, and stability mostly influence nanocarrier penetration and drug delivery to skin. In particular, thermoresponsive nanogels which can release loaded drugs preferentially above a distinct temperature, represented an attractive approach to improve the selectivity of anti-inflammatory therapies. In addition soft, thermoresponsive nanogels were found to penetrate deeply within the stratum corneum, the outermost skin barrier, changing its permeability and improving drug penetration. Penetrated nanogels were internalized by skin cells in both epidermis and dermis. Interestingly, also significant percentage of antigen presenting cells were found to be associated with nanocarriers depending on the degree of skin barrier disruption. These observations could further be developed for specific targeting approaches in order to increase drug delivery to key cell populations.