Biofunctionalization of titanium surfaces for dental implants: osteogenic, anti-microbial and tribocorrosion resistant surfaces

PhD thesis in Biomedical Engineering

Seismic-resistant building practices resulting from local seismic culture

Considering that vernacular architecture may bear important lessons on hazard mitigation, this chapter focuses on the European Mediterranean countries and studies traditional seismic-resistant architectural elements and techniques that local populations developed to prevent or repair earthquake damage. This area was selected as a case study because, as a highly seismic region, it has suffered the effect of many earthquakes along the history and, thus, regions within this area are prone to have developed a Local Seismic Culture. After reviewing seismic resistant construction concepts, a wide range of traditional construction solutions that, in many cases, have shown to improve the seismic performance of vernacular constructions of these regions is presented, as a contribution to the general overview of retrofitting building systems provided in this book. The main motivation is that most of these techniques can be successfully applied to preserve and to retrofit surviving examples without prejudice for their identity.

Light responsive multilayer surfaces with controlled spatial extinction capability

Multilayer systems obtained using the Layer-by-Layer (LbL) technology have been proposed for a variety of biomedical applications in tissue engineering and regenerative medicine. LbL assembly is a simple and highly versatile method to modify surfaces and fabricate robust and highly-ordered nanostructured coatings over almost any type of substrates and with a wide range of substances. The incorporation of polyoxometalate (POM) inorganic salts as constituents of the layers presents a possibility of promoting light-stimuli responses in LbL substrates. We propose the design of a biocompatible photo-responsive multilayer system based on a Preyssler-type POM ([NaP5W30O110]14â ) and a natural origin polymer, chitosan, using the LbL methodology. The photo-reduction properties of the POM allow the spatially controlled disruption of the assembled layers due to the weakening of the electrostatic interactions between the layers. This system has found applicability in detaching devices, such as the cell sheet technology, which may solve the drawbacks actually found in other cell treatment proposals.

Biomimetic superhydrophobic surfaces patterned with wettable spots as implantable chips for in vivo high-content 3D biomaterials response assessment

"Tissue engineering: part A", vol. 21, suppl. 1 (2015)

Micro/nano-structured superhydrophobic surfaces in the biomedical field: part I: basic concepts and biomimetic approaches.

Inspired by natural structures, great attention has been devoted to the study and development of surfaces with extreme wettable properties. The meticulous study of natural systems revealed that the micro/nano-topography of the surface is critical to obtaining unique wettability features, including superhydrophobicity. However, the surface chemistry also has an important role in such surface characteristics. As the interaction of biomaterials with the biological milieu occurs at the surface of the materials, it is expected that synthetic substrates with extreme and controllable wettability ranging from superhydrophilic to superhydrophobic regimes could bring about the possibility of new investigations of cellâ material interactions on nonconventional surfaces and the development of alternative devices with biomedical utility. This first part of the review will describe in detail how proteins and cells interact with micro/nano-structured surfaces exhibiting extreme wettabilities.

Estudo da ligação entre componentes estruturais de GFRP (glass fiber reinforced polymer) e componentes estruturais em betão

Dissertação de mestrado integrado em Engenharia Civil

Superhydrophobic surfaces as a tool for the fabrication of hierarchical spherical polymeric carriers

Hierarchical polymeric carriers with high encapsulation efficiencies are fabricated via a biocompatible strategy developed using superhydrophobic (SH) surfaces. The carries are obtained by the incorporation of cell/BSA-loaded dextran-methacrylate (DEXT-MA) microparticles into alginate (ALG) macroscopic beads. Engineered devices like these are expected to boost the development of innovative and customizable systems for biomedical and biotechnological purposes.

Antibiofilm strategies in the food industry

Biofilms in food processing plants represent not only a problem to human health but also cause economic losses by technical failure in several systems. In fact, many foodborne outbreaks have been found to be associated with biofilms. Biofilms may be prevented by regular cleaning and disinfection, but this does not completely prevent biofilm formation. Besides, due to their diversity and to the development of specialized phenotypes, it is well known that biofilms are more resistant to cleaning and disinfection than planktonic microorganisms. In recent years, a considerable effort has been made in the prevention of microbial adhesion and biofilm formation on food processing surfaces and novel technologies have been introduced. In this context, this chapter discusses the main conventional and emergent strategies that have been employed to prevent bacterial adhesion to food processing surfaces and thus to efficiently maintain good hygiene throughout the food industries.

Synthetic biology approaches to shape bacteriophages towards Pseudomonas aeruginosa biofilm control

Dissertation for Ph.D. degree in Biomedical Engineering.