Desenvolvimento e caracterização de scaffolds de quitosana/Cissus verticillata (L.) Nicolson & C.E. Jarvis.

Abstract

The systems of controlled clearance of pharmaco present several advantages when compared to others of conventional dosages and, among the most used polysaccharides in the development of these systems can be highlighted the chitosan which, due to being biocompatible and biodegradable, has aroused the interest of the scientific community for its use in the development of structures where pharmaco may be incorporated. The plant species Cissus verticillata (L.) Nicolson & C.E. Jarvis is popularly known as insulin and, several pharmacological studies have indicated its hypoglycemic action, thereby justifying its applicability in the care of patients with diabetes. Thus, this work aimed to develop and characterize chitosan scaffolds with different concentrations of Cissus verticillata (L.) Nicolson & C.E. Jarvis, in order to access its possible use in patients with type 2 diabetes mellitus. The method consisted in the solubilization of the chitosan in acetic acid, addition of the vegetal drug, and obtaining of the scaffolds by means of the freeze drying technique. The samples were characterized by the analysis of Fourier transformed infrared spectroscopy (FTIR), X-ray Difractometry (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectrometer (EDS), Optical Microscopy (OM), Wettability Test, Compression Test, Thermogravimetric Analysis (TGA) and the Differential Scanning Calorimetry (DSC), Degree of swelling with PBS and artificial saliva and Enzymatic Biodegradation Test. The chemical study was carried out by the FTIR identified all the bands characteristic of the studied materials and the morphological study revealed, in the scaffolds, the formation of a tridimensional structure with interconnected pores. The EDS technique revealed the presence of the chemical elements Carbon, Oxygen and Nitrogen, in addition to Magnesium, Silicon and Calcium present in the vegetable drug. The degree of swelling demonstrated that the averages of the masses were correspondingly higher in the swollen form than in the dry condition, being this swelling greater when the samples were immersed in artificial saliva, when compared to the PBS solution. The wettability test demonstrated that the scaffolds had their hydrophilicity increased with the incorporation of the vegetal drug and, the compression test, confirmed their greater resistance to deformation. The TG/DTG analysis demonstrated that the vegetal drug reduced the thermal stability of the scaffolds. From the biodegradation test, was found that the scaffolds suffered a greater degradation in contact with the PBS solution than in PBS/Lysozyme; and that, in the assessment periods, the artificial saliva did not promote biodegradation to the structures. The incorporation of the vegetable drug to the scaffolds was confirmed by means of the results obtained in the de FTIR, DRX, MEV, OM, Degree of swelling, wettability and compression tests, TG/DTG and DSC tests. Therefore, it can be concluded that there was the formation of scaffolds with favorable morphological and physicochemical properties for obtaining a system of controlled clearance of pharmaco.