Citrate Mediated Wet Chemical Synthesis of Fe Doped Nanoapatites: A Model for Singly Doped Multifunctional Nanostructures

The structurally forgiving nature of the apatite lattice may be employed to synthesize functional nano-hydroxyapatite (nHA) particles with calcium site substitution by metal atom doping. In this work we present an effective green synthetic methodology to synthesize equiaxed and highly dispersed Fe(III)-doped multifunctional nHA particles by controlled aging of a calcium phosphate precursor. It was seen that doping in the HA lattice, while employing this wet chemical technique, does not induce a structural change even with 30 mol. % Fe-substitution. The Fe(III)-doped nanoparticles exhibited both magnetic and luminescent properties. The magnetic properties were measured employing magnetometry and SQUID. The Fe doped nHA particles also exhibited green fluorescence under UV excitation. While single property modulation in nHA has been previously shown by doping with metal atoms, herein we show that it is possible to design nHA particles, and perhaps others, with multifunctional properties with only one dopant.