In this paper, new steps toward a etter understanding and utilization of high-pressure high-temperature nanodiamonds (NDs) containing nitrogen-vacancy (NV) centers have been taken. NV–-related long-term luminescence of oxygenated particles increased in comparison to plasma hydrogenated NDs’ NV– luminescence. The optically detected NV– electron spin resonance process can be also significantly affected by ND termination. For H-terminated ND particles the NV– to NV0 conversion energy is lower than the NV– excitation energy, so that the delocalized triplet electrons can be more easily released from the original positions and drawn to the electron-attracting localities in the material. The final result of this study was application of luminescent NDs in cells, showing the detectability of luminescent NDs in a standard confocal microscope and ND subcellular distribution in the cells by TEM.
