FORMULATION AND EVALUATION OF CURCUMIN LOADED THIOLATED POLYMER COATED LIPOSOMES FOR APHTHOUS ULCERS

Abstract

Aphthous ulcers or Recurrent Aphthous Stomatitis (RAS) are inflammatory lesions of mucous lining of mouth associated with redness, swelling and occasional bleeding from affected area(s). Curcumin, a herbal drug was selected due to its antioxidant, anti-inflammatory, antimicrobial and wound healing ability. Present study deals with formulation, optimization and evaluation of curcumin loaded liposomes for local drug delivery as liposomes have property to get concentrated in inflamed areas. Efficacy of liposomes was enhanced in terms of mucoadhesion, retention in the buccal mucosa and sustained release of drug by coating them with Thiolated Karaya gum. Curcumin loaded liposomes, prepared using thin film hydration method were optimized by 3² factorial design using Design Expert Software. Batch F8 having entrapment 75.1±0.94 % and controlled the release of curcumin up to 12 h was considered optimized and was coated with thiolated karaya gum to get TKF8. Successful coating was evident from TEM images, increase in particle size from 129.86 ± 9.1 nm to 152.39 ± 1.3 nm, zeta potential from negative to positive -10.5 mV to 9.55mV. TKF8 showed better mucoadhesion by absorbing 6.98 % more amount of mucin and also had ability to concentrate in the buccal mucosa for 24 h as observed using exvivo studies. It can be attributed to positively charged thiolated polymer interacting with negatively charged sialic acid residues in the mucus. Drug release from F8 and TKF8 was sustained for 12 h and 24 h respectively and they followed diffusion controlled release (Peppas model). This formulation can be efficient therapeutic strategy for apthous ulcers which would provide relief to the patients.