Topical cellulose nanocrystals-stabilized nanoemulgel loaded with ciprofloxacin HCl with enhanced antibacterial activity and tissue regenerative properties

Spray-dried cellulose nanocrystals (CNC) were investigated as a potential stabilizer for the preparation of nanoemulsion gels (nanoemulgels) loaded with ciprofloxacin hydrochloride to act as dual-role gels capable of stimulating the tissue regeneration as well as inhibition of microbial growth. The selected nanoemulgel (NEG/2) which was composed of 10% w/w linoleic acid and 4% w/w CNC had a particle size of 203.2 nm, drug content of 95.5%, zeta potential of −31.1 mV and polydispersity index of 0.34. Comparing the in-vitro drug release results, NEG/2 attained the highest percentage release efficiency with the most sustained behavior (release rate = 18.9%/h). The selected nanoemulgel possessed a thixotropic, shear thinning behavior favorable for dermal preparations. Results also revealed that NEG/2 showed improved antibacterial activity against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa bacteria in addition to improved cytocompatibility and cell regenerative characters on human dermal fibroblasts. In conclusion, the proposed formulation offered a safe, biocompatible and promising approach for injured skin care.