Design and evaluation of chitosan/gellan gum hybrid in situ forming implants for delivering ciprofloxacin for periodontitis treatment.

Periodontitis is a chronic oral inflammatory disease commonly caused by bacterial infection that affects oral health. Ciprofloxacin (CIP) is an antimicrobial agent with low water solubility (0.067 mg/mL at 25 °C, pH 7.5) and poor permeability. This research aims at fabricating chitosan/gellan gum hybrid extended release in-situ forming implants (CG-IFIs) loaded with CIP/Poloxamer 407 solid dispersion for treatment of periodontitis. Solid dispersions were loaded into chitosan/gellan gum matrix, cross linked with 2% w/v sodium bicarbonate. Upon exposing the implants to body temperature, a sol-gel transition occurs. The implants were evaluated for gelation time, injectability, in-vitro drug release, surface morphology and erosion rate. Results indicated that formulation (CG-IFI3) comprising 1% (w/v) chitosan, 0.2% (w/v) gellan gum, and a 2:1 w/w ratio of Poloxamer 407/CIP solid dispersion exhibited an appropriate gelation time (12 ± 2.5 min), favourable flow rate (0.83 ± 0.05 ml/min), and sustained drug release over two weeks. The selected formulation (CG-IFI3) was injected intragingivally into the mandibular incisive region of a rat model after induction of periodontitis via the ligature method. After 15 days of treatment, CG-IFI3 significantly reduced periodontal inflammation, vascular congestion, and tissue infiltration. These findings suggest that CG-IFI3 is a promising localised delivery system for managing periodontitis.