TY: THES T1 - Biomedical microelectromechanical (BioMEMs) systems to tissue engineering: applications in hard tissues A1 - Magueta, Adriana Fernandes N2 - Metals and their alloys are the materials most commonly used in medical applications for bone support due to their biocompatibility and mechanical properties. Nevertheless, these materials do not stimulate bone regeneration and, over time, release metallic ions into the human body, which in large numbers is toxic. One way to overcome this problem is to use coatings with biocompatible and biodegradable materials capable of stimulating bone regeneration. In this work, 316 stainless steel alloy was used as the component capable of withstanding the loads applied to bone and poly(L-lactic acid) (PLLA) was chosen as a coating due to its biocompatible, biodegradable and piezoelectric properties, simulating the collagen present in the bone. In this work the adhesion between 316 SS and PLLA was studied. 316 SS functionalization was carried out through a chemical process, silanization, and the respective quantification of silanes was performed. The PLLA films were deposited by spin-coating, with different thicknesses, varying the solution concentrations and the number of deposited layers, and with different degrees of crystallization. The results showed that the functionalization of the metal substrate with silanes is effective and efficient in the adhesion of PLLA films to 316 SS. The degree of adhesion, as measured by the standard tape test depends, besides the functionalization of the substrate, on the film thickness, the concentration of the polymer solution and on the degree of crystallization of the polymeric film. The best results were achieved for the thinner films. However, for crystallized films, adhesion has improved for larger thicknesses. When immersed in PBS, the films did not stand out, being the best results for the crystallized films. With this study it was possible to produce and characterize stable PLLA coatings on 316 SS substrates, with suitable adhesion to medical applications, which represents a promising contribution to the exploitation of the electrical polarization of these plaforms for bone tissue regeneration and for the study of other biomedical platforms constituted by two different materials. UR - https://ria.ua.pt/handle/10773/25803 Y1 - 2018 PB - No publisher defined