Synthesis of water-soluble γ-aminopropyl triethoxysilane-capped ZnO:MgO nanocrystals with biocompatibility

ZnO:MgO nanocrystals have been synthesized by a sequential preparative procedure and capped with γ-Aminopropyl triethoxysilane (APTES), thereby rendering the surface of the nanocrystals hydrophilic and the particles water-soluble. Orthogonal experiment was employed to optimize the correlated parameters of the reaction of capping ZnO:MgO nanocrystals with APTES. The effects of the quantity of APTES, reaction time, and reaction temperature on the aqueous stability of APTES-capped ZnO:MgO nanocrystals were investigated by orthogonal experiment and their optimal values were determined to be: 0.25 mmol, 60 min, and 25 °C, respectively. The water-soluble APTES-capped ZnO:MgO nanocrystals emit strongly in the visible region on excitation by UV radiation and are stable over extended periods. The aqueous-stability of the nanocrystals is attributed to the exposed hydrophilic groups (–NH2, –OH). Furthermore, hemolysis was performed to evaluate the biocompatibility of the nanocrystals. Hemolytic results indicate that APTES-capped ZnO:MgO nanocrystals have good biocompatibility, which is especially important for ensuring their potential in biomedical applications.