Development and evaluation of Norfloxacin microparticulate polymeric carriers for enhanced wound healing

This present study aimed to develop and evaluate topical gels of norfloxacin polymeric microspheres as an adjunct strategy for improved treatment of wounds.

Norfloxacin microspheres were formulated through quasi-emulsion solvent diffusion method using polymers, i.e., Ethocel 4 cps and Eudragit RLPO and stabilizer; polyvinyl alcohol. Microspheres were characterized for particle size, entrapment efficiency, surface morphology, DSC, antibacterial studies. To make the formulation more acceptable to patients, these microspheres were incorporated into Carbopol gels and assessed for in vitro and ex vivo permeation, in vivo wound contraction studies in Wistar rats.

The developed microspheres ranged in size from 10-60μm with 86.88±0.08% drug entrapment efficiency. SEM depicted discrete, smooth and spherical microspheres with no evidence of drug crystals. DSC confirmed molecular dispersion of norfloxacin in polymeric matrix of microspheres. In vitro antibacterial studies can be related to release of norfloxacin for extended periods from microspheres. Microspheres were incorporated into Carbopol Ultrez 10NF gels, which exhibited acceptable physiochemical characteristics. In vitro and ex vivo permeation from topical gels revealed extended release and deeper deposition of norfloxacin into rat abdominal skin respectively after 8h. Primary skin irritation studies performed on rats revealed the topical gels were non-irritant. In vivo studies using full thickness excisional wound healing model revealed greater wound contraction with complete wound closure within 12 days.

The promising results exhibited potential of topical gels of norfloxacin microspheres as adjunct therapy for managing chronic wounds by providing extended antimicrobial action, improved wound healing and may reduce application frequency.