Clinacanthus nutans-Based Mucoadhesive Films for Oral Ulcers

Abstract

Current pharmaceutical products for oral ulcers are topical creams and pastes containing corticosteroids, when the excessive use increases various complications. Thailand's National List of Essential Herbal Medicines (NLEM), the recommended only dosages of Clinacanthus nutans (Burm. f.) Lindau (C. nutans) in a solution for treatment of oral ulcer. This experimental research aims to develop the C. nutans mucoadhesive films. The weights of polymethacrylates L-100 or E-100; polyvinyl alcohol (PVA); and sodium alginate (ALG-Na) or Carbopol 934P, were varied, given glycerine or PEG-400 as the plasticizer, giving rise to 72 initial formulations. The physicochemical characteristics and analysis were subsequently carried out and the results compared. Given the poor performance of PEG-400, the PEG-400 film formulations were excluded from further analysis. The findings showed that only the A3, B3 and A9 glycerine-based film formulations yielded the functional oral mucoadhesive films, where A and B denote polymethacrylates L-100 and E-100. To enhance the film performance, further experiments were carried out with the A3, B3 and A9 films by incorporating both ALG-Na and Carbopol 934P in the film formulations in the ratios of 1: 1 and 2: 1. The experimental results revealed that the A3.1 is the best physicochemical characteristics, with the dissolution time of 300 minutes, the in-vitro mucoadhesive time in excess of 6 hours and the lupeol bioactive content as high as 142.01 μg/ml. The A3.1 formulation, consisting of 22.5g polymethacrylates E-100, 11.25g ALG-Na, 11.25g Carbopol 934P and 45g PVA, is functionally ideal for pilot scale of the C. nutans oral mucoadhesive films.