Synthesis of calcium phosphate coatings and nanoparticles using supersaturated solutions for biomedical applications

Abstract

Calcium phosphates have long been used as biocompatible and osteoconductive biomaterials. Calcium phosphate-based nanocomposites with additional biofunctionality can be synthesized via coprecipitation in supersaturated calcium phosphate solutions supplemented with bioactive substances (e.g., proteins, DNA, trace elements, etc.). In this review paper, we will describe our supersaturated solution processes with and without the aid of pulsed laser irradiation for the synthesis of calcium phosphate-based thin layers and nanoparticles immobilizing selected bioactive substances. Depending on the type of bioactive substances and synthetic conditions, the resulting thin layers and nanoparticles exhibit a variety of physicochemical properties and biological functions (e.g., antibacterial activity, gene delivery capability, cell adhesion property, etc.). The calcium phosphate-based thin layers have the potential as biofunctional coating agents for biomaterials, whereas calcium phosphate-based nanoparticles have the potential as delivery carriers of therapeutic and diagnostic agents. Our synthetic processes are simple, performed under normal pressure and temperature, and require no toxic reagents, and thus, would be useful as production tools of such biofunctional calcium phosphate-based materials for diverse biomedical applications.