Multi-drug hybrid delivery systems with distinct release profiles based on gelatin/collagen containing vesicles derived from block copolymers.

ABSTRACT

Hybrid delivery systems can release multiple drugs with different profiles and have several applications, including skin dressing. In this work, the co-solvent technique was used for the preparation of nanometric vesicles based on poly(styrene-b-ethylene oxide) block copolymer (BCPVs) containing adapalene (AD). The BCPVs were incorporated into collagen and gelatin matrices together with free AD and silver sulfadiazine (SSD). The AD content of BCPVs and their release capacity were analyzed by using ultraviolet-visible spectroscopy (UV-Vis). The gelatin and collagen matrices were evaluated for their ability to release AD and SSD through an in vitro release study. The obtained results confirmed that the production of empty and AD-loaded BCPVs was viable. The degree of AD encapsulation in BCPVs was 9.0% and the in vitro test revealed a constant, slow, and prolonged release of AD content from AD-loaded BCPVs. The combination of free and encapsulated multiple drugs in hybrid delivery systems based on gelatin and collagen matrices was shown to act as a skin dressing that combined the progressive release of large amounts of drugs within the first hours of use (to restrict infection) with a more prolonged and slow release of AD to enhance skin healing.