Ciprofloxacin-intercalated layered double hydroxide-in-hybrid films as composite dressings for controlled antimicrobial topical delivery.

Films based on biopolymers and loaded with antimicrobial agents are convenient pharmaceutical dosage forms for topical application. Inorganic carriers loaded with these agents lead to composite materials, which combined with polymers produce further functionality. Here, hybrid composite films based on layered double hydroxide (LDH) and hyaluronan (HS) as ciprofloxacin (Cip) delivery systems were studied as an alternative for prophylaxis and treatment of opportunistic infections in wounds. Cip-intercalated Zn-Al LDH (LDH-Cip), with high drug loading and crystallinity, were obtained by a precipitation at variable pH method, and then included in a HS dispersion for obtaining the hybrid composite films by solvent casting. Physicochemical characterization of films showed that a composite material where the HS acted as matrix and LDH-Cip aggregates acted as filler were obtained. LDH-Cip were uniformly dispersed along the (LDH-Cip)/HS films, which exhibited roughness in their surface, increasing their swelling capacity in PBS pH = 5.8. Controlled releases of Cip toward PBS at pH = 5.8 and 7.4 were obtained, and the best fits for the release profiles were found with Higuchi and Korsmeyer-Peppas models, respectively. (LDH-Cip)/HS films exhibited antimicrobial activity against S. aureus. These films would then provide sustained release of Cip after topical administration, maintaining a suitable level of antibacterial activity, combined with the wound healing properties of the HS. The interesting properties shown by the (LDH-Cip)/HS films make them a promising alternative for application in skin wounds.