Highly biocompatible multifunctional hybrid nanoparticles based on FeO decorated nanodiamond with superior superparamagnetic behaviors and photoluminescent properties.

The multifunctional nanostructures with superparamagnetic and luminescent properties undergo revolution in the field of bio-nanotechnology. In this article, we reported a facile and efficient one-step modified co-precipitation method to load superparamagnetic FeO nanoparticle on oxidized nanodiamond (Ox-ND). Subsequently, the as-prepared Ox-ND/FeO hybrid nanoparticle was surface functionalized with vinyltrimethoxysilane (VTMS) to enhance its compatibility with organic media. The structure, morphology, magnetic, and optical properties of the nanohybrid were systematically investigated. The results confirmed successful loading of crystalline FeO on the surface of Ox-ND. Ox-ND/FeO multifunctional hybrid nanoparticle presented strong superparamagnetism (with a saturation magnetization of 67 emu/g at room temperature) and photoluminescence (blue emission) with good chemical reactivity. PrestoBlue assay indicated great biocompatibility of silanized Ox-ND/FeO in MCF-7 cells even at high concentrations, e.g. 7.2 mg/mL. The hybrid nanoparticle synthesized in this study potentially opens doors for high contrast imaging and targeted delivery applications.