Analysis of submicrometric hydroxyapatite powder as obtained by drilling and milling pork bones

Abstract Hydroxyapatite is a commonly used biomaterial in medical and dental implants. While it can be synthesized, it is often extracted from bovine bone. However, challenges persist in the extraction process, such as ensuring reproducibility in particle size and distribution, crystallinity, and cost-effective large-scale production. This study employs porcine bone drilling for the first time, complemented by mechanical milling and calcination, and aims to determine the route that allows obtaining submicrometric HA powders with high crystallinity and the smallest possible particle size. Characterization of the obtained powders was performed using X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), and Fourier-transform infrared analysis (FTIR). The resulting material in the sequence drilling-milling-calcination shows high crystallinity and purity, although larger particle sizes were observed compared to those reported in the literature. Additionally, highly pure HA with particle sizes ranging from 160 to 510 nm (mean: 277.3 nm) was obtained via the drilling-calcination-milling sequence. This particle size range represents a significant improvement in size reduction compared to other mechanical methods reported in the literature.