Synergistic effects of carbohydrate polymers on the performance of hybrid injectable bone pastes

[Display omitted] •Injectable pastes are synthesized using carbohydrate polymers and HA/β-TCP.•Degradation rate of the paste is in inverse relationship with organic material content.•Increasing in polymers content can act as a controller of the degradation rate.•The presence of carbohydrate polymers enables injectability even at low forces.•GA12HB and GC4HB samples are suitable for bone treatment as optimized pastes. During the past few years, invasive surgery operations using injectable systems, have been applied for the treatment of osteoporosis bone defects. In this research, different injectable pastes made from natural polymer such as gelatin (Ge), carboxymethyl cellulose (CMC), alginate (Alg) and inorganic materials containing hydroxyapatite (HA) and biphasic calcium phosphate (BCP) were studied. BCP was fabricated via solid state reaction. Evaluation of BCP crystalline structure confirmed the presence of tricalcium phosphate (TCP) and HA phases. The morphology of calcium phosphate powders and the paste showed fine particles and homogeneous distribution, respectively. Consistency, injectability, washout and the rheology behavior of pastes were evaluated too. According to the results, the pastes consisted of considerable values of calcium phosphate content (about 65%) and injectability of 84% and 91% with acceptable degradation in PBS, were found for Gel/0.4% CMC and Gel/1.2% Alg pastes, respectively. It could be concluded that the addition of carbohydrate polymers (CMC and Alg) to the formulation of samples could be an effective way to adjust the final performance of the hybrid injectable bone pastes.