New nanostructured apatite-type (Na ⁺,Zn ²⁺,CO ₃ ²⁻)-doped calcium phosphates: Preparation, mechanical properties and antibacterial activity

Nanoparticles with the sizes in the range (20–30) nm of apatite-type Na ⁺,Zn ²⁺,CO ₃ ²⁻-doped calcium phosphates were prepared from aqueous solution of Na ⁺-Ca ²⁺-Zn ²⁺-NO ₃ ⁻-CO ₃ ²⁻-PO ₄ ^3- system at molar ratios Ca ²⁺/PO ₄ ^3- =1.67, CО ₃ ²⁻/РО ₄ ^3- = 1, Zn ²⁺:Ca ²⁺ = 1:100 or 2:100. The elemental analysis showed growth of Zn ²⁺ content in composition of samples from 0.61 to 1.95 wt% at increasing of Zn ²⁺ amount in an initial solution. According to FTIR and Raman data, B-type substitution of PO ₄ ³⁻ by CO ₃ ²⁻ realized in apatite-type calcium phosphates. The mechanical properties study for prepared phases showed the dependence of Young's modulus and compressive strength on Zn ²⁺ amount in their composition. Growth of S. epidermidis after the contact with synthesized apatite containing Na ⁺ (0.25 wt%), Zn ²⁺ (0.61 wt%) and CO ₃ ²⁻ (1.18 wt%) was significantly delayed with an extension of lag time from 1 to 13–14 h. The prepared sample can be considered as a new prospective biomaterial with antibacterial potential.