| Popis: |
One of the used approaches to improve the biological and physicochemical properties of scaffolds is ionic substitutions with key role ions. Octacalcium phosphate (OCP) is considered a precursor of biological apatite and has shown remarkable regenerative properties. In this study, Sr, Mg, Ag-substituted OCP powders were prepared by precipitation method with varying substitution content (0, 1 and 2.5 mol%). Prepared powder samples were composed of OCP and amorphous calcium phosphate, while lattice parameters of OCP changed depending on the size of Sr2+ (0.113 nm), Mg2+ (0.072 nm) and Ag+ (0.0128 nm) ions. Substitution with Sr2+ and Ag+ ions increased, while with Mg2+ ion decreased the thermal stability of OCP. Substituted OCP crystals have shown characteristic plate-like morphology with homogeneously distributed ions. To obtain multifunctional scaffolds, Sr, Mg, Ag-substituted OCP powders have been mixed to determine the synergic properties of substituents. The substituted ions enhanced protein adsorption capacity and antibacterial activity towards Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli. Highly porous scaffolds based on obtained powders and carboxymethyl chitosan have been prepared by the feeze-gelation technique. The scaffolds have shown a highly porous structure, with interconnected pores and high stability in simulated body conditions. |
