Graphene onto medical grade titanium: an atom-thick multimodal coating that promotes osteoblast maturation and inhibits biofilm formation from distinct species

Abstract

The time needed for the osseointegration of titanium implants is deemed too long. Moreover, the bacterial colonization of their surfaces is a major cause of failure. Graphene can overcome these issues but its wet transfer onto substrates employs hazardous chemicals limiting the clinical applications. Alternatively, dry transfer technique has been developed, but the biological properties of this technique remain unexplored. Here, a dry transfer technique based on a hot-pressing method allowed to coat titanium substrates with high-quality graphene and coverage area >90% with a single transfer. The graphene-coated titanium is cytocompatible, did not induce cell membrane damage, induced human osteoblast maturation (gene and protein level), and increased the deposition of mineralized matrix compared to titanium alone. Moreover, graphene decreased the formation of biofilms from Streptococcus mutans, Enterococcus faecalis and even from whole saliva on titanium without killing the bacteria. These findings confirm that coating of titanium with graphene via a dry transfer technique is a promising strategy to improve osseointegration and prevent biofilm formation on implants and devices.

Keywords:

• Carbon
• osteogenesis
• differentiation
• infection
• osseointegration
• Raman

Disclosure statement

The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript.

Additional information

Funding

This research is supported by the National Research Foundation, Prime Minister’ Office, Singapore, under its Medium Sized Centre Program and by the grants from the Singapore Ministry of Education, Singapore (Academic Research Fund Tier 1, R-221-000-091-112), National University Health System, Singapore (NUHS Bench-to-Bedside, R-221-000-074-515 and NUHS Open Collaborative Research Grant NUHS O-CRG 2016 Oct -25).