Deakin Research

Institute for Frontier Materials

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Process takes textile recycling to new level

A new process to separate blends of cotton-polyester material provides a major breakthrough for recycling textile and other waste.

A solution to pollution?

Bio-plastics could help slash global plastic consumption.

Small fibres bring big opportunities

A 'Skilling the Bay' $500,000 grant will help Geelong tap into the rapidly growing nanofibre market.

Working together

New partnership between Deakin and Geelong manufacturers.

Our Research

Titanium and its alloy scaffolds

An image of Porous Ti scaffolds and osteoblast cells growing on their surface

Porous Ti scaffolds and osteoblast cells growing on their surface.

Titanium and some of its alloys are widely accepted by human bone tissue as load-bearing implants due to their relative mechanical properties, superior biocompatibility and excellent corrosion resistance, in comparison to other metals such as SUS316L stainless steel and Co-Cr-Mo alloy. However, they are often much stiffer than human bone. This mismatch of elastic modulus causes stress shielding, leading to implant loosening and eventual failure. Development of new Titanium alloys with low elastic modulus and using biocompatible titanium in a porous structure are promising to provide a solution for this challenge.

Research focuses on:

  • Understanding and study biocompatibility of the elements of titanium alloys and their interaction with biological cells.
  • Design and develop new biocompatible titanium alloys with low elastic modulus for biomedical applications.
  • Scaffold new developed titanium alloys to porous biomaterials for hard tissue engineering.

Biodegradable magnesium alloys

Magnesium alloys are receiving increasing attention as new biodegradable implant materials for orthopaedic applications. Mg is a natural ionic presence with significant functional roles in biological systems, and may stimulate the growth of new bone tissue. Moreover, Mg and its alloys are lightweight, with mechanical properties similar to those of natural bone. The elastic modulus and compressive strength of Mg alloys are closer to those of natural bone than other commonly used metallic implants. In particular, Mg and its alloys are biodegradable in the human body, where biodegradation of the Mg alloy implants involves the formation of a soluble, non-toxic oxide that is safely excreted in the urine. However, there are three major concerns in using pure Mg and currently existing Mg alloys for load-bearing implant materials. One of the challenges is that pure Mg possesses poor mechanical performance. Its low mechanical strength and elastic modulus cannot satisfy the mechanical property requirements of an implant material because it cannot sustain the rigours of the daily activity of patients after implantation into the body. The second challenge is that currently existing Mg alloys possess low corrosion resistance and therefore degrade too quickly in the human body. Therefore, to develop new Mg alloys using strengthening alloying elements becomes an indispensable approach.

Research focuses on::

  • Understand and study biocompatibility of the elements of magnesium alloys and their interaction with biological cells.
  • Design and fabricate new biocompatible Magnesium alloys with appropriate biodegradable rate for bone implant and heart stent materials.
  • Understand the biodegradation mechanism of magnesium alloys.
  • Surface modification on biocompatible magnesium alloys to satisfy the appropriate biodegrade rate and the requirements for biomedical applications.
An image of Cell adhesion on the Mg alloys after cell culture for 24 h: (a) Mg5Zr, (b) Mg1Zr2Sr and (c) Mg2Zr5Sr

Cell adhesion on the Mg alloys after cell culture for 24 h: (a) Mg5Zr, (b) Mg1Zr2Sr and (c) Mg2Zr5Sr


Biocompatible and bioactive surfaces

An image of TiO₂ nanotube layer on Ti

TiO₂ nanotube layer on Ti

Bone cell functions such as cell growth, spreading and proliferation are influenced by the cell adhesion on implant materials, which affects the integration of implants to host bone cells and tissues, and further determines whether an implantation succeeds or fails.

The cell adhesion strength at the cell-implant interface is an important indicator of the biocompatibility of the implant. However, evaluating biocompatibility, especially assessing, predicating and quantifying the adhesion strength between bone cells and implants remains a challenge. Moreover, there is still a clear gap in the knowledge of the interactions between bone cells and implant surfaces, to date.

Research focuses on:

  • Understand and study the interaction of the surface of metallic biomaterials with biological cells.
  • Develop micro and nano surface modifications on metallic biomaterials to enhance the biocompatible and bioactivity of metallic biomaterials, which include to enhance the direct bonding between implants and host tissues and the growth ability of new hard tissues.

Deakin University acknowledges the traditional land owners of present campus sites.

11th February 2014