The aim in using bioglasses in implants is to encourage the body to mend tissue damage using its own repair mechanisms, rather than using biologically inert transplant materials, such as metal implants.
Through the use of neutron scattering, scientist Bob Newport from the University of Kent used ISIS to visualise the atomic structure of bioglass.
“Neutrons are of enormous value for understanding the atomic scale structure of materials.” said Professor Newport. “The atomic structure is intimately connected to the bioactivity of the material and how easily the glass dissolves in body ﬂuids such as blood plasma and saliva. The detailed structural knowledge we have obtained is a prerequisite for optimizing the material design.”
Results from studies of bioglasses at ISIS are being used to produce a tougher bioglass-polymer hybrid for potential use in hip and knee replacements. With an average life expectancy of 80 years in the UK, bioactive materials are increasingly relevant.
“The problem with glasses is that they are brittle.” says Dr Julian Jones, Imperial College London. “Bioglass-polymer hybrids have interpenetrating molecular networks of polymer and silica (glass), and are unique in that they allow bespoke design of mechanical properties and degradation rate.”
Polymer hybrids perform much better under biomechanical loads than bioglass alone, and are compatible with the internal environment of the body. They form a platform, or template, that can be used in the regeneration of tissues such as bone, and are successful because they can be highly tailored to their application.
At ISIS, it was found that alternating the elements used in the composition of bioglass changes its solubility properties once in the body. Dr. Julian Jones has used these results to produce new types of hybrid materials with therapeutic properties.
Bioglass polymer hybrids display controlled decomposition in bodily fluids so that the platform can be maintained until the role performed by the bioglass, such as stimulation of new bone growth, can be transferred to the newly formed tissue growing in its place. ISIS has also been used to help in the optimisation of bioglasses as anti-bacterial coatings and for use as drug delivery materials.
Professor Bob Newport, University of Kent
Dr Julian Jones, Imperial College London
Research date: July 2012
A structural investigation of the alkali metal site distribution within bioactive glass using neutron diﬀraction and multinuclear solid state NMR
RA Martin, HL Twyman, GJ Rees, JM Smith, ER Barney, ME Smith, JV Hanna, RJ Newport
Phys Chem Chem Phys (in press, 2012)
DOI: 10.1039/c2cp41725a http://pubs.rsc.org/en/content/articlepdf/2012/cp/c2cp41725a
Silica-Gelatin hybrids with tailorable degradation and mechanical properties for tissue regeneration
O Mahony, O Tsigkou, C Ionescu, C Minelli, L Ling, R Hanly, ME Smith, MM Stevens, JR Jones
Advanced Functional Materials 20(22) (2012) 3835.
Image: Julian Jones and Wouter van den Bergh, Imperial