Thiago Bizerra Fideles

Porous Hydroxyapatite Scaffolds by Polymer Sponge Method

This study aimed to develop porous hydroxyapatite scaffold for bone regeneration using the replica of the polymeric sponge technique. Polyurethane sponges were used with varying densities to obtain the scaffolds. The results indicate the porous HA scaffolds developed in this study as potential materials for application as bone substitutes to have high porosity (> 70%), chemical composition, interconnectivity and pore sizes appropriate to the bone regeneration.

Biodegradable Chitosan Scaffolds: Effect of Genipin Crosslinking

Currently researchers has pointed chitosan as one of the viable alternatives for application as scaffolds in tissue regeneration, mainly due to its availability, biocompatibility, biodegradability and ability to chemical modifications, among them, the crosslinking. With the growing number of investigations of crosslinking agents from natural sources and its applicability, this work focuses on the development and microstructural characterization of chitosan scaffolds and chitosan crosslinked with genipina using the technique of freeze drying. Solutions were prepared with chitosan concentration of 2% (w / t), and genipin 0.15% (w / t) and 0.3% (w / t). These were frozen at-20 ° C and ≈ 196 ° C, and lyophilized. The effect of different concentrations of genipin and freezing rates of the solutions in the porous architecture of the scaffolds were evaluated by Scanning Electron Microscopy (SEM), Optical Digital Microscopy 2D and 3D (OM) and testing the Degree of Swelling (DS). The SEM analysis revealed the formation of a three dimensional structure with pores and / or channels interconnected, influenced by the freezing rate and addition of crosslinking agent, these variables also influence the absorption capacity of the scaffolds. It was observed by OM, the effectiveness of the crosslinking with genipin, through points of fluorescence presented.

Morphological Evaluation of Chitosan/Curcumin Beads and Powder: Effect of the Methanol as a Solvent

Curcumin is a polyphenolic component of Curcuma longa, highlighting in the literature by presenting medicinal properties such as: antioxidant, anti-inflammatory, antibacterial, antiparasitic, antimalarial and anticancer activities. From this, it has been used together with curcumin, chitosan, a biodegradable polymer of natural origin, in order to encapsulate curcumin from a polymer system. Thus, this study aimed to evaluate the morphological behavior of beads and powder chitosan/curcumin, by the Optical Microscopy (OM) technique in the presence of the solvent (methanol). From the pictures, it was noticed that the beads have in their external structure the presence of the drug in a punctual manner, but a more homogeneous internal region. Regarding the powder, it was observed that curcumin was well distributed and involved by chitosan, proving the good interaction between them. In the presence of the solvent, the beads and the powder showed a good distribution of curcumin.

Development and Characterization of Chitosan Membranes as a System for Controlled Release of Piperine

Among the variety of polymers used as drug carriers, chitosan has received attention in the fields of medicine and pharmacy by being a nontoxic, biocompatible and biodegradable copolymer. Piperine is a natural alkaloid, has various pharmacological activities such as anti-inflammatory, analgesic, antipyretic, hepatoprotective and antitumor when combined with chitosan has better bioavailability and more effectiveness. This work aims to prepare and characterize chitosan / piperine membranes obtained by the solvent casting method. The membranes were characterized by Spectroscopy Fourier Transform Infrared (FTIR), X-ray Diffraction (DRX) and Scanning Electron Microscopy (MEV). From the results obtained it can be concluded that the process described was effective in obtaining the system chitosan/piperine indicating its potential for studies of controlled release of drug.

Hydroxyapatite/Biopolymers Composite Scaffolds for Bone Tissue Engineering

The application of a hybrid composite consisting of biopolymer and calcium phosphate, similar morphology and properties of natural bone, may be a way to solve the problem of the fragility of ceramics without reducing its mechanical properties, retaining the properties of biocompatibility and high bioactivity. This work aims at the preparation and characterization of three-dimensional scaffolds composite HA / biopolymers (chitosan and gelatin). The freeze-drying technique was employed in this study to obtain these frameworks and partial results showed the effectiveness of this method. This involved the study of structural, chemical and morphological frameworks, in order to direct the research suggested the application. The X Ray Diffraction (XRD) and infrared spectroscopy and Fourier transform (FTIR) results confirmed the formation of hydroxyapatite (HA) phase and the presence of characteristic bands of HA and biopolymers in all compositions. The microstructure of the scaffolds study conducted by Scanning Electron Microscopy (SEM) revealed the formation of longitudinally oriented microchannels with interconnected pores. In all compositions the porous scaffolds showed varying sizes and mostly larger than 100μm, and is therefore considered materials with potential for application in bone tissue engineering.

Characterization of the Snail’s Carapace Collected at Coast of Brazilian’s State of Paraíba

Calcium carbonate (CaCO3) is a ceramic of strong economic potential, given the versatility of its application in industry in many different areas. Protective shells of marine snails of the Brazilian coast were analyzed in this study, to verify the content of calcium carbonate available in this type of material. The samples were collected at Bessa´s Beach located in the João Pessoa’ coast Capital of Paraíba state, northern Brazil. The collection occurred during the month of February 2008; the sample was processed into powder and it was examined by X-ray Fluorescence (XRF), X-ray diffraction (XRD) and Infrared Spectroscopy with Fourier Trasformating (FTIR). The material was also submitted to heat treatment at 110°C and characterized by same techniques. The results confirmed the presence of a high content of calcium carbonate in the samples (over 95%,) which has not changed with the heat treatment used. It was presents the morphologies calcite and aragonite with prevalence of the second, both showing high levels of crystallinity. From the results obtained, calcium carbonate of the coast Paraíba has a potential application like bioceramic.