Controlled thermal growth of magnesium phosphate nanograins and evaluation of their in vitro biocompatibility

Biogenic inorganic particles promote cellular metabolism and tissue growth, but their long-term accumulation can impede tissue repair. Here, we synthesized magnesium phosphate bioceramics (MPBs) via a precise thermal treatment, reacting equimolar magnesium acetate and sodium polyphosphate at 70 °C. The resulting MP was divided into three groups and calcined at 400 °C, 600 °C, and 800 °C. Comprehensive characterization using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS) revealed distinct structural and compositional properties. The physicochemical properties of MPBs varied with calcination temperature, significantly influencing surface morphology, crystallinity, and solubility. Notably, MP synthesized at 600 °C exhibited a nanograin structural size (∼150 nm) with a zeta potential value of −22.04 ± 2.6 mV, confirming distinct crystal lattices and excellent colloidal dispersibility. The bioresorbable MPBs exhibited an effective biointerface, supporting fibroblast adhesion, proliferation, and infiltration confirmed by an in vitro cell study. Sustained Mg ion release contributed to fibroblast regeneration by providing essential minerals for cellular metabolism. This study emphasizes the attractiveness of MPBs as biodegradable scaffolds with superior biological properties, positioning them as cost-effective biomaterials for bioengineering and biomedical applications. • Thermal treatment significantly influenced the surface topography of magnesium phosphate (MPBs), leading to variations in grain morphology and surface roughness. • Controlled calcination at 600 °C facilitated the formation of distinct nanograin structure of MPBs. • MPBs exhibited a zeta potential of −22.04 ± 2.6 mV, indicating strong colloidal stability and reduced tendency of particle aggregation. • The bioceramic scaffold of MPBs demonstrated excellent biocompatibility with NIH/3T3 cells.