蛋壳是一种生物矿物，主要由CaCO3形成的方解石相和渗透的有机基质（1-3.5重量％）组成。将蛋壳中的方解石颗粒转化为磷酸钙（磷灰石）微纳米颗粒，将废弃的蛋壳材料重新利用于具有潜在生物医学应用的材料中，实现循环经济原则。先前获得这些颗粒的方法主要包括两个步骤，第一个步骤涉及对蛋壳进行焙烧处理。在本研究中，采用一锅法水热法研究了100-200 °C范围内的直接转化，使用具有化学计量的P/CaCO3比例的悬浊液，以K2HPO4作为P试剂，以及未经处理和经NaClO处理的蛋壳颗粒（Ø < 50 μm）以去除表面有机物质。在未经处理的组中，完全转化温度为160 °C，大多数颗粒呈六角形板状形态，最后出现中央孔洞。在处理组中，这种替代发生在180 °C，生成颗粒状（球状）磷灰石纳米颗粒。与MG-63人骨肉瘤细胞和m17.ASC小鼠间质干细胞共培养后，蛋壳颗粒和磷灰石微纳米颗粒与细胞相容，并促进了m17.ASC细胞的成骨分化。该研究结果对于设计和制造具有骨诱导性能的生物相容性微结构材料在骨组织工程和牙科应用中具有重要意义。

The eggshell is a biomineral consisting of CaCO3 in the form of calcite phase and a pervading organic matrix (1-3.5 wt.%). Transforming eggshell calcite particles into calcium phosphate (apatite) micro-nanoparticles opens the door to repurposing the eggshell waste as materials with potential biomedical applications, fulfilling the principles of the circular economy. Previous methods to obtain these particles consisted mainly of two steps, the first one involving the calcination of the eggshell. In this research, direct transformation by a one-pot hydrothermal method ranging from 100-200 °C was studied, using suspensions with a stoichiometric P/CaCO3 ratio, K2HPO4 as P reagent, and eggshells particles (Ø < 50 μm) both untreated and treated with NaClO to remove surface organic matter. In the untreated group, the complete conversion was achieved at 160 °C, and most particles displayed a hexagonal plate morphology, eventually with a central hole. In the treated group, this replacement occurred at 180 °C, yielding granular (spherulitic) apatite nanoparticles. The eggshell particles and apatite micro-nanoparticles were cytocompatible when incubated with MG-63 human osteosarcoma cells and m17.ASC murine mesenchymal stem cells and promoted the osteogenic differentiation of m17.ASC cells. The study results are useful for designing and fabricating biocompatible microstructured materials with osteoinductive properties for applications in bone tissue engineering and dentistry.