Mucoadhesive films based on polyvinyl alcohol and bioactive compounds for oral administration: structural characterization and mucoadhesive properties

In this study, two well known plant species, Matricaria chamomilla L. and Viola tricolor L., were characterized in terms of their polyphenolic and antioxidant profiles. 1:1, 1:2 and 2:1 mixtures ratioswere obtained from the alcoholic extracts. The plant extracts were analysed by high performance liquid chromatography coupled with mass spectrometry (HPLC-MS) and by FolinCiocalteu, CUPRAC and DPPH methods. Comparing the values of the bioactive principles contained in each mixture, as well as the antioxidant character, the mixture Matricariae flos/Violae tricolor flos 2:1, with an inhibition percentage of 84.28 & PLUSMN; 1.36%, was chosen to be incorporated into a mucoadhesive polymeric film. The formulated polymeric films were realized by incorporating 5% and 8% polyvinyl alcohol, 5% and 10% plant extract, respectively. The mucoadhesive films pH ranged between the normal salivary pH values (6.899 & PLUSMN; 0.016 and 7.045 & PLUSMN; 0.017), high folding strength and high tensile strength. According to the performed analyses and the plant extract yield operation from the polymer films, the films incorporating 5% polymer and 10% plant extract, respectively 5% polymer and 5% extract exhibited excelent results.