Effect of propolis and polymer content on mechanical, bioadhesive and biological properties of nanostructured film forming platforms for topical drug delivery

Film form systems (FFS) composed of thermoresponsive and bioadhesive polymers have shown properties for the improvement of topical application. FFS are easy for administration, can increase the local residence time, control the drug delivery and improve the skin permeation. Propolis displays important biological properties like anticancer, healing, antimicrobial, antioxidant and can improve the structuring of FFS. It is a safe bioactive compound for wound healing and the treatment of skin diseases. However, propolis displays drawbacks for administration. The aim of this work was to evaluate the effect of polymeric and propolis composition on morphological, rheological, bioadhesive, drug release and skin permeation properties of designed FFS. In-vitro cytotoxicity, antitumoral and wound healing activity were also evaluated. Formulations composed of different amounts of polymers and propolis were proposed. The presence of propolis enhanced the bioadhesiveness and structuring of FFS. They displayed excellent capacity to form nanostructured film, displaying controlled propolis delivery and improved skin permeation. FFS were not cytotoxic and displayed in-vitro antitumoral activity and stimulated the cell migration. The selected preparations containing propolis extract (12%, w/w) and carbomer 974P or polycarbophil (0.25%, w/w) indicate a potentially advantageous role to be topically administered and suggest they are promissory formulations for clinical evaluation.