Abstract

Nitrogen vacancy centers (NVCs) in nanodiamonds have recently been attracting much attention as a new fluorescent probe. NVC is an atomic-sized defect paired with a nitrogen atom and the adjacent vacancy of a carbon atom in the diamond lattice. It is known that fluorescence from NVC-containing nanodiamonds is markedly stable in contrast to organic and semi-conducting fluorescent probes commonly used in cell and in vivo observations. A notable property is that the fluorescence from NVC is dependent on a spin degree of freedom in the ground states, and the fluorescence intensity can be manipulated by microwave (MW) irradiations in optically detected magnetic resonance (ODMR). By using this property that the fluorescence intensity of NVC, but not that of other sources, changes upon resonant MW irradiation at 2.87 GHz, we reported a selective imaging method to completely eliminate extraneous fluorescence in real-time microscope observations, and demonstrated successful observations of nanodiamonds in a living HeLa cell, Caenorhabditis elegans, and a mouse¹⁾.

© 2015 Japan Society of Applied Physics, Optical Society of America