Calcium phosphate nucleation on cellulose fabrics

Nonwoven cellulose (regenerated, oxidized) fabrics were coated with hydroxy carbonated apatite (HCA) using a procedure based on a biomimetic method. Simulated body fluid (SBF) with a high degree of supersaturation (5xSBF) was applied to accelerate the biomimetic formation of bonelike apatite on the cellulose fabrics. After creating calcium phosphate nuclei on the cellulose fibers in a first 5xSBF with high Mg²⁺ and HCO₃⁻ concentrations, the cellulose fabrics were additionally soaked in a second 5xSBF which was optimized with respect to accelerated crystal growth by reduced Mg²⁺ and HCO₃⁻ concentrations. The hydroxy carbonated apatite (HCA) layer thickness increased from 6 μm after 4 h of soaking in the latter solution to 20 μm after 48 h. The amount of CO₃²⁻ substituting PO₄³⁻ in the hydroxyapatite (HA) lattice of the precipitates can be varied by changing the soaking time.