Development of BMP-2 immobilized polydopamine mediated multichannelled biphasic calcium phosphate granules for improved bone regeneration

- Surface modification of BCP granules with polydopamine and BMP-2.
- Enhanced cell viability for B-PD-MCG and PD-MCG compared to MCG.
- Improved bone regeneration efficacy in B-PD-MCG after 6 weeks of implantation.
- B-PD-MCG system-promising injectable bone substitute for applications.

In the present study, the bone morphogenetic protein-2 (BMP-2) was loaded onto a polydopamine-coated biphasic calcium phosphate (BCP) granule system which could be effectively used as an injectable bone substitute (IBS) for improved bone regeneration. The surface of BCP granules was first coated with polydopamine (PD-MCG) and then BMP-2 growth factor was immobilized onto the PD-MCG by a conventional method. The results showed that BMP-2 was successfully immobilized into polydopamine-coated granules and about 87% of BMP-2 was retained on the granular surface for 30 days. Invitro and invivo studies showed enhanced cell viability and superior bone formation conferred by B-PD-MCG granules compared with PD-MCG and MCG. The percent healing capacity (BV/SV) of the three samples tested was found to be 1.64 ± 0.04, 1.4 ± 0.02 and 1.12 ± 0.03 for B-PD-MCG, PD-MCG and MCG, respectively.