2020 Volume 27 Issue 2 Pages 185-190
It has become clear that temperature plays a major role in many life phenomena. However, little is known about the intracellular temperature, and the relationship between regenerative function and intracellular temperature of stem cells. In this study, fluorescent nanodiamond (FND) that can be applied as an excellent quantum sensor was used for stem cell labeling. Then, the relationship between the regenerative function of stem cells and the intracellular temperature of stem cells was evaluated by a sensing the optically detected magnetic resonance (ODMR) activity of NV centers in FNDs. FNDs could label adipose tissue-derived stem cells (ASCs) at high efficiency with 24 h incubation, and no cytotoxicity was observed in ASCs labeled with less than 500 µg/mL of FNDs. The ODMR of NV centers in FNDs was confirmed at approximately 2.87 GHz with a characteristic fluorescence spectrum, and the intracellular temperature of living ASCs during several days of culturing could be precisely measured. Moreover, the intracellular temperature was found to influence the production of growth factors and the degree of differentiation into adipocytes and osteocytes. These data suggest that NV centers in FNDs can be used to investigate the relationship between intracellular temperature and cellular functions.
