resumo
A series of seven alkali-free silica-based bioactive glasses (SBG) with ZnO and/or SrO additives (in concentrations of 0-12 mol%) were synthesized by melt-quenching, aiming to delineate a candidate formulation possessing (i) a coefficient of thermal expansion (CTE) similar to the one of titanium (Ti) and its medical grade super alloys (crucial for the future development of mechanically adherent implant-type SBG coatings) and (ii) antibacterial efficiency, while (iii) conserving a good cytocompatibility. The SBGs powders were multi-parametrically evaluated by X-ray diffraction, Fourier transform infrared and micro-Raman spectroscopy, dilatometry, inductively coupled plasma mass spectrometry, antibacterial (against Staphylococcus aureus and Escherichia coli strains) suspension inhibition and agar diffusion tests, and human mesenchymal stem cells cytocompatibility assays. The results showed that the coupled incorporation of zinc and strontium ions into the parent glass composition has a combinatorial and additive benefit. In particular, the Z6S4 formulation (mol%: SiO2-38.49, CaO-32.07, P2O5-5.61, MgO-13.24, CaF2-0.59, ZnO-6.0, SrO-4.0) conferred strong antimicrobial activity against both types of strains, minimal cytotoxicity combined with good stem cells viability and proliferation, and a CTE (similar to 8.7 x 10(-6) x degrees C-1) matching well those of the Ti-based implant materials.
palavras-chave
SIMULATED BODY-FLUID; BIOACTIVE GLASS; THERMAL-EXPANSION; ANTIMICROBIAL ACTIVITY; ESCHERICHIA-COLI; CHEMICAL-COMPOSITION; HYDROGEN-PEROXIDE; SILICATE-GLASSES; IMMUNE-RESPONSE; STRONTIUM
categoria
Materials Science
autores
Popa, AC; Fernandes, HR; Necsulescu, M; Luculescu, C; Cioangher, M; Dumitru, V; Stuart, BW; Grant, DM; Ferreira, JMF; Stan, GE
nossos autores
Hugo Alexandre Gonçalves da Rocha Fernandes
Investigador Júnior
José Maria da Fonte Ferreira
Professor(a) Jubilado(a)Grupos
G3 - Materiais Eletroquímicos, Interfaces e Revestimentos
G5 - Materiais Biomiméticos, Biológicos e Vivos
agradecimentos
A.C.P., M.N., C.B. and G.E.S. are grateful for the financial support of the Romanian National Authority for Scientific Research and Innovation, CNCS-UEFISCDI, in the framework of projects PN-II-RU-TE-2014-4-0180, PN-III-P1-1.1-TE-2016-1501, and Core Programme PN18-110101. The support of CICECO-Aveiro Institute of Materials (Ref. UID/CTM/50011/2013), funded by FEDER funds through the Operational Programme Competitiveness Factors (COMPETE 2020) and the Portuguese Foundation for Science and Technology (FCT) is acknowledged. H.R.F. is grateful for the Post-Doctoral Grant (SFRH/BPD/110883/2015) from the Fundacao para a Ciencia e a Tecnologia (FCT), Portugal. B.W.S. and D.M.G. acknowledge that this work was supported by the Engineering and Physical Sciences Research Council [grant number EP/K029592/1] via the Centre for Innovative Manufacturing in Medical Devices (MeDe Innovation). The authors would like to gratefully acknowledge Saul Vazquez Reina (University of Nottingham) for assistance with ICP-MS analysis.