Desenvolvimento de membranas de gelatina para liberação controlada de fármacos em ulcerações de mucosa oral.

Abstract

Recurrent Aphthous Stomatitis (RAS) is one of the most common pathological oral mucosal lesion, of variable size and duration, typically found in the non-keratinized oral mucosa. Topical agents are the first treatment choice for these kind of ulcerations, because they are effective and safe. However, it present as a challenge the effectiveness of drug delivery at the local site of injury. Topical medications are easily removed from the target area and this limitation may be restricted by the development of membranes which remain in prolonged contact with the mucosa and gradually release the drug into the lesion. For this research, gelatin membranes incorporated with triamcinolone acetonide and chamomile extract were develop inisolation and with the association of both drugs in a membrane. With 4% solution concentration of gelatin associated with 0.8%, concentration of glycerin was prepared and 0.0048% of triamcinolone acetonide and / or 0.48% of chamomile extract was incorporate. The final solution was spilled into petri dishes and the solvent was evaporated in a kiln with air circulation at 30 °C. The membranes were crosslinked by three techniques: glutaraldehyde solution, ultraviolet radiation and genipine solution; therefore, characterized by Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), Fourier Transform Infrared Spectroscopy (FTIR), in vitro biodegradation assay and swelling degree measurements, study of Triamcinolone Acetonide controlled release and its association with the chamomile extract,wettability test and, finally, bioadhesion test. About the SEM analysis, the gelatin membranes with chamomile extract a homogeneous surface were observed with total incorporation of the extract, while in the membranes with triamcinoloneacetonide could be perceived small agglomerates of the drug. The variables presented very close micrograph profiles when compared through the AFM technique, except for the membrane with the incorporation of the chamomile extract, which presented more homogeneity surface. Genipine-crosslinked membranes showed the swelling degree and the in vitro biodegradation profile more satisfactoryfor the intended use than when cross-linked by Ultraviolet radiation. Through the solution with 0.0005% genipine concentration and exposure time of 1 minute was reached the desired period of membrane permanence in artificial saliva before its complete biodegradation. The presence of chamomile on the gelatin membrane incorporated with triamcinolone acetonide supported not only in the therapy but also in the modification of the drug release profile, promoting a slower rate release. The membrane that presented less hydrophilicity and more bioadhesion was the one with the incorporation of triamcinolone acetonide. The variables were homogeneous in their drug release behavior and presented low standard deviation, fact that emphasizes the coherent methodology used for this research. The membranes produced reached the expectations of this research, being the variable with the incorporation of both drugs the most adequate for the intended use.