ABSTRACT
This chapter focuses on the various strategies in the preparation, structure, and properties of naked and surface-functionalized inorganic nanoparticles (NPs) and their toxicity profile. NPs display, by themselves, unique features due to their optical, electronic, and magnetic properties. Optical imaging is a very sensitive molecular imaging modality, although it is hampered by the very limited tissue penetration and low spatial resolution. Therefore, it is necessary to improve the visualization of diseases and elucidate NPs’ biological behavior by combining diagnostic imaging modalities. Magnetic nanoparticles, in particular iron oxide NPs, possess unique properties such as superparamagnetism, high coercivity, low Curie temperature, and high magnetic susceptibility along with inherent biocompatibility and inexpensiveness. The desired surface functionalization should satisfy criteria such as good water stability and chemical functionality to maintain the NPs’ physical and chemical properties, as well as biocompatibility. Gold nanoparticles offer a suitable platform for multifunctionalization with different biomolecules for the specific binding and detection of small molecules and biological targets.
