@article {Almeida2016,
	title = {A biocompatible hybrid material with simultaneous calcium and strontium release capability for bone tissue repair},
	journal = {Materials Science and Engineering: C},
	volume = {62},
	year = {2016},
	month = {03/2016},
	pages = {429-438},
	chapter = {429},
	abstract = {<p>The increasing interest in the effect of strontium in bone tissue repair has promoted the development of bioactive materials with strontium release capability. According to literature, hybrid materials based on the system PDMS{\textendash}{}SiO2 have been considered a plausible alternative as they present a mechanical behavior similar to the one of the human bone. The main purpose of this study was to obtain a biocompatible hybrid material with simultaneous calcium and strontium release capability. A hybrid material, in the system PDMS{\textendash}{}SiO2{\textendash}{}CaO{\textendash}{}SrO, was prepared with the incorporation of 0.05 mol of titanium per mol of SiO2. Calcium and strontium were added using the respective acetates as sources, following a sol{\textendash}{}gel technique previously developed by the present authors. The obtained samples were characterized by FT-IR, solid-state NMR, and SAXS, and surface roughness was analyzed by 3D optical profilometry. In vitro studies were performed by immersion of the samples in Kokubo{\textquoteright}s SBF for different periods of time, in order to determine the bioactive potential of these hybrids. Surfaces of the immersed samples were observed by SEM, EDS and PIXE, showing the formation of calcium phosphate precipitates. Supernatants were analyzed by ICP, revealing the capability of the material to simultaneously fix phosphorus ions and to release calcium and strontium, in a concentration range within the values reported as suitable for the induction of the bone tissue repair. The material demonstrated to be cytocompatible when tested with MG63 osteoblastic cells, exhibiting an inductive effect on cell proliferation and alkaline phosphatase activity.</p>
},
	keywords = {Biocompatible, Hybrid materials, peer-reviewed, Strontium},
	issn = {09284931},
	doi = {10.1016/j.msec.2016.01.083},
	author = {Almeida, J. Carlos and Andr{\'a}s Wacha and Gomes, Pedro S. and Alves, Lu{\'\i}s C. and Fernandes, M. Helena Vaz and Salvado, Isabel M. Miranda and Fernandes, M. Helena R.}
}
@article {128,
	title = {PDMS-SiO2 hybrid materials {\textendash} A new insight into the role of Ti and Zr as additives},
	journal = {Polymer},
	volume = {72},
	year = {2015},
	month = {2015/08/18/},
	pages = {40 - 51},
	abstract = {The last two decades have seen a remarkable growth in the design of new hybrid materials applied to different areas, from photonics to biomaterials, together with new coating materials with self-cleaning features. Among the various systems studied, the PDMS-SiO2 system remains as a good basis for further developments by adding other compounds such as transition metals. In this work, a detailed study of the influence of titanium or zirconium in the chemical structure and final microstructure of such hybrids was made. It was concluded that, due to the lower reactivity of the titanium alkoxide during the sol{\textendash}gel preparation process, titanium is preferably located on the surface of secondary particles of silica, unlike the zirconium, which being more reactive, positions on the surface of the primary particles. This difference leads to xerogels with dissimilar characteristics and morphologies.},
	keywords = {CREDO, Hybrid materials, Sol{\textendash}gel, Structure},
	isbn = {0032-3861},
	url = {http://www.sciencedirect.com/science/article/pii/S0032386115300732},
	author = {Almeida, J. Carlos and Andr{\'a}s Wacha and B{\'o}ta, A. and Alm{\'a}sy, L. and Vaz Fernandes, M. Helena and Marga{\c c}a, Fernanda M. A. and Miranda Salvado, Isabel M.}
}
