At present, the technology we have for preparing the essential materials for bone healing requires the use of high temperature and harmful chemicals, which would most likely cause side effects. For scientists and engineers, this was a call for improvement.
Hydrogels are polymeric biomaterials that are structurally alike with living tissues and are able to absorb water. Because of these properties, hydrogels are used for the delivery of cells so that they can assist in the regeneration of lost or defective tissues. One limitation of these polymeric compounds would be that their pores are very small. This gives the cells that they carry a lower chance of survival during transport. The formation of new tissue would then be limited as well.
In a publication in Nature Communications, bioengineers and dentists from UCLA explain how clay-enhanced hydrogel is a step up from current bone repair techniques.
Through intercalation, the researchers inserted the positively charged hydrogels into layers of negatively charged clay. This process yielded a clay-enhanced hydrogel that the polymeric structure of a hydrogel and the porosity of clay. The porosity would contribute in better facilitation of the transport of cells, therefore assisting in bone formation and healing, the researchers believed. After producing their new biomaterial, they used a photo-induction technique to convert its phase into a gel so that it can be in injectable form.
The composite material was injected into a mouse that had a defect in its skull, which no longer heal itself. In six weeks' time, it proved successful when the hydrogel caused naturally occurring stem cells to migrate and promote bone healing.
Lead researcher Min Lee, who is also a professor of biomaterials science at the UCLA School of Dentistry a member of the Jonsson Comprehensive Cancer Centre, explained the possibility of expanding the range of applications for their development. "This research will help us develop the next generation of hydrogel systems with high porosity and could greatly improve current bone graft materials," he said. "Our nanocomposite hydrogel system will be useful for many applications, including therapeutic delivery, cell carriers and tissue engineering." Lee also mentioned how this noninvasive procedure could potentially replace rather invasive surgical procedures in the future.
Of course, further studies on the effects of the new composite biomaterial on the migration process and their detailed functions need to be conducted in the future, UCLA says.
