<p>This work describes a biomimetic approach for synthesizing multi-doped calcium phosphate nanoparticles (CaP NPs) that closely mimic the structure and composition of bone mineral. Inspired by bone remodeling, hydroxyapatite (HAp), used as a combined calcium and phosphorus source, was first dissolved in an acidic medium and then re-precipitated in simulated body fluid (SBF), serving as a physiologically relevant source of trace elements. The results showed that multi-doped amorphous calcium phosphate (ACP) formed within the first few minutes and gradually transformed into poorly crystalline carbonated hydroxyapatite over a 21-day maturation period. This extended observation provides valuable insights into the incorporation of trace elements and their role in the maturation of bone-like mineral phases. The resulting nanoparticles exhibited low crystallinity and nanometric dimensions, along with increased surface area and porosity. They also demonstrated excellent biocompatibility with MG63 osteoblasts and effectively promoted osteogenic responses in human mesenchymal stromal cells. Overall, this strategy offers valuable insights for designing biomimetic CaP NPs inspired by living tissue to support future applications in hard tissue regeneration.</p> Graphical Abstract <p></p>