Physico-chemical, mechanical and cytotoxicity characterizations of Laponite®/alginate nanocomposite

•Laponite/alginate nanocomposite was developed for biomedical applications.•Adding laponite into alginate enhanced alginate mechanical strength.•The nanocomposite was non-toxic, and its extracts enhanced cell viability.•Due to its injectability, the composite can be used as a drug carrier.

Combining clay minerals containing silica with polymers can improve the performance of polymers in biomedical applications by the synergistic combination of physico-chemical and biological properties of both phases. In this study, Laponite® — a synthetic biocompatible and biodegradable silicate clay mineral, was combined with alginate to improve alginate mechanical and biological characteristics. The physico-chemical properties (porosity, degradation, swelling, crystalline structure, compressive strength, and injectability) and biological responses (cytotoxicity and cell morphology) of the Laponite/alginate nanocomposites were investigated in the study. The results showed that the incorporation of Laponite into alginate significantly enhanced alginate compression strength without hindering its injectability when the percentage of clay mineral was below 50%. The prepared clay polymer nanocomposites (CPN) were not toxic and the viability of cells cultured in its extract was indeed higher than alginate alone. However, these prepared CPN poorly supported cell adhesion, probably due to the high degradation rate of the materials.