Insights into corrosion behaviour of uncoated Mg alloys for biomedical applications in different aqueous media

• Type: Article in International Scientific Journal
• Date: 2021

Authors

Neves, CS (Author) Other; Sousa, I (Author) Other; Freitas, MA (Author) Other; Moreira, L (Author) Other; Costa, C (Author) Other; Teixeira, JP (Author) Other; Sonia Fraga (Author) FMUP; Pinto, E (Author) Other; Agostinho Almeida (Author) FFUP; Scharnagl, N (Author) Other; Zheludkevich, ML (Author) Other; Ferreira, MGS (Author) Other; Tedim, J (Author) Other

Journal

Title: JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T

Vol. 13

Pages: 1908-1922

ISSN: 2238-7854

Indexing

ISI Web of Knowledge - 5 Citations

Scopus - 6 Citations

Other information

Authenticus ID: P-00V-2A6

DOI: 10.1016/j.jmrt.2021.05.090

Abstract (EN): MgCa and MgGd series of alloys are often reported as promising candidates for biomedical applications. In the present study, cytotoxicity and corrosion behavior of Mg1Ca and Mg10Gd alloys in different electrolytes (NaCl, PBS, MEM) have been investigated in order to make a direct comparison and understand the mechanisms behind their performance. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) were employed to analyze corrosion processes depending on media composition, whereas X-Ray diffraction (XRD) and scanning electron microscopy (SEM) were used to evaluate crystalline structure, phase composition and surface morphology of the corroded substrates after immersion in the different electrolytes. Moreover, cytotoxicity of the Mg alloys was assessed using the WST-1 reduction and lactate dehydrogenase (LDH) release assays in L929 mouse fibroblasts. The electrochemical results showed that Mg1Ca has a lower degradation rate when compared to Mg10Gd, due to the lower microgalvanic effects and the presence of Ca as an alloying element. Furthermore, the corrosion activity is reduced in MEM, for both alloys, when compared to NaCl and PBS. The cytotoxicity assays revealed that Mg10Gd was cytotoxic in all the conditions tested, while the toxicity of Mg1Ca was low. Overall, these findings show that Mg1Ca alloy presents a higher corrosion resistance and biocompatibility and is a promising material to be used in biomedical implants.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 15