Here we showed it was possible to use specific interactions between clay nanoparticles and bisphosphonates tethered to a polymer, to generate self-assembling hydrogels with enhanced mechanical properties. Because of the specific way bisphosphonates bind to clay, other key binding sites are preserved to allow nanoclay localisation of active pharmaceutical agents such as BMP-2.
Nanoclay particles can self-assemble into gels under physiological conditions and bind growth factors for enhanced and localized efficacy. Here we show the ability to localize and enhance the activity of BMP-2 to achieve ectopic bone formation at doses within physiological sub-microgram per ml range of concentrations and at approximately 3000-fold lower than those employed in clinical practice.
Here, the potential to harness the gel-forming properties of nanoclay to generate injectable bioactive microenvironments for osteogenesis is demonstrated. A diffusion/dialysis gelation method allows the rapid formation of stable transparent gels from injectable, thixotropic nanoclay suspensions in physiological fluids. Further encapsulation of skeletal stem cell-containing populations in the diffusion gels significantly enhances osteogenic protein expression compared with 3D pellet culture controls.
The aim of this study first-on-human study was to test whether nanoclay gels cause irritation when applied on healthy human skin. The study confirmed that nanoclay caused no prolonged increase in inflammation and preserved skin barrier function better than another widely used topical gel. This study confirms that nanoclay is not an irritant and is suitable for therapeutic interventions at the skin surface.
It is known that nanoclays can directly stimulate bone-forming activity in skeletal stem cells independently of any added drugs or bioactive molecules. This is often assumed to be down to the chemical influence of the metal ions that are released by nanoclays as they degrade in a cell. However, this study showed that the bioactive effects of clay on cells are not due to its chemical components, but rather to the physical influence of the clay particles themselves.
This study reported the application of a nanoclay composite gel optimised for 3D printing of skeletal stem cells to promote blood vessel formation and enhance bone formation in vivo.
This paper reported the application of nanoclays to develop a novel light-curable nanocomposite bioink for 3D skeletal regeneration. The composite allowed high fidelity printing of viable cells and active growth factors and stimulated blood vessel formation.
Here, we explored the capacity of nanoclay gels to deliver VEGF, a molecule that stimulates the growth of blood vessels. The results indicate that the nanoparticles enhance the VEGF efficacy by retaining it at the implantation site for a prolonged period.
A review article examining the literature describing the intrinsic bioactivity of nanoclay and how it can be harnessed to activate stem cells for repair.
Here, we developed a nanoclay composite gel optimised for 3D cell printing. The addition of nanoclay was shown to allow plotting of hydrogel scaffolds with unusually high accuracy in clinically relevant dimensions and shapes.
This review article explored previous studies seeking to harness clays in medicine and lays out a vision for harnessing nanoclay interactions with polymers, drugs and cells for regenerative medicine.