Mechanical, tribological and biological properties of novel 45S5 Bioglass® composites reinforced with in situ reduced graphene oxide. (January 2017)

• Record Type: Journal Article
• Authors: Li, Zhong; Khun, Nay Win; Tang, Xiu-Zhi; Liu, Erjia; Khor, Khiam Aik
• Is Part Of: Journal of the mechanical behavior of biomedical materials. Volume 65(2017)
• Page Start: 77
• Page End: 89
• Publication Date: 2017-01
• Subjects: Bioactive glass -- Graphene -- Spark plasma sintering -- Fracture toughness -- Tribological properties -- Biocompatibility; Biomedical materials -- Periodicals; Biomedical materials -- Mechanical properties -- Periodicals; Biomedical materials; Biomedical materials -- Mechanical properties; Periodicals; Electronic journals; 610.28
• DOI: 10.1016/j.jmbbm.2016.08.007
• Languages: English
• ISSNs: 1751-6161

Abstract

Abstract: 45S5 Bioglass ® (45S5) is one of the most widely used biomaterials in ceramic-based bone graft substitutes by virtue of its excellent biocompatibility and bioactivity. However, the fracture toughness and wear resistance of 45S5 have to be improved to extend its applications in load bearing orthopedic implants. The current study reports the first use of graphene nanoplatelet (GNP) to enhance the fracture toughness and wear resistance of 45S5. Composite powders with four different loadings of graphene oxide (GO), i.e. 0, 0.1, 0.5 and 1 wt%, were sintered by spark plasma sintering (SPS) at a relatively low temperature of 550 °C, during which in situ thermal reduction of GO took place. It was found that by adding 0.5 wt% GO to the 45S5 powder, the fracture toughness of the sintered pellets was increased by 130.2% while friction coefficient and specific wear rate were decreased by 21.3% and 62.0%, respectively. Furthermore, the viability of MG63 cells grown on the GNP-incorporated pellets was comparably high to that of the cells grown on the pure 45S5 pellets. As compared with the pure 45S5 leachates, the media conditioned by the GNP/45S5 pellets fabricated from the composite powder with 1 wt% GO could enhance both the proliferation and viability of MG63 cells. It is thus envisioned that the GNP-reinforced 45S5 is a highly promising material for fabricating mechanically strong and biocompatible load-bearing bone implants. Graphical abstract: Highlights: SPS used to reduce graphene oxide in situ and consolidate the composites. Fracture toughness of sintered 45S5 increased by 130.2% with 0.5 wt% GO addition. Adding 0.5 wt% GO reduced the friction coefficient by 21.3% and specific wear rate by 62.0%. Comparably high viability observed for MG63 cells grown on pure and composite pellets. GNP/45S5 leachates generally led to faster proliferation and higher viability of MG63 cells than pure 45S5 leachates.