A necessidade de novos recursos em cardiologia tem direcionado a Engenharia de Tecidos ao desenvolvimento de vasos sanguíneos artificiais que atendam aos requisitos do organismo. Neste trabalho, estruturas tubulares de celulose bacteriana (CB) foram produzidas e sua degradação in vitro foi avaliada. Através de microscopia eletrônica de varredura constatou-se que não houve alterações significativas na microestrutura e morfologia das fibras de CB após ensaios de degradação. Os ensaios de degradação em soluções fisiológicas PBS e salina revelaram uma degradação substancialmente baixa após 20 semanas. A baixa velocidade de degradação dos vasos é de grande importância, visto que o processo para a formação de novos vasos (angiogênese) demanda tempo.

The need of new techniques in cardiology has driven Tissue Engineering towards the development of artificial blood vessels that fulfill the requirements of the organism. In this work bacterial cellulose (BC) tubular structures were produced and their degradation in vitro was evaluated. No significant changes in microstructure and BC fiber morphology were observed by scanning electron microscopy after degradation tests. Degradation tests in physiological solutions (PBS and saline) revealed a very low degradation after 20 weeks. A low degradation rate of artificial vessels is important, since the process of new blood vessel formation (angiogenesis) demands time.

A natural bentonite sample from Argentina was activated by sulfuric acid in different concentrations (20 and 40 wt%) and different contact time (120 and 210 min), at the same temperature (90 °C) . The ratio of the mass of clay to the volume of acid solution was 1:10 (w/v). These materials were tested to verify its bleaching (decolorization) capacity of soybean oil, which was compared to a standard commercial bleaching material Fulmont Premiere. Differential thermal analysis and thermogravimetric techniques, infrared spectrometry and chemical analysis showed that the acid activation modified the clay material structural properties. Bleaching capacity was found to be dependent on the acid concentration and treatment time used. The activated Argentine material showed superior bleaching performance compared to the commercial clay used by vegetable oil refiners.