Fig. 5

Characterization of the photo stability of diamond-based color marker and Alexa Fluor 555-conjugated. a Fluorescence traces under continuous 532 nm wavelength laser illumination of Alexa Fluor 555-conjugated (green marker) and fNDs containing nitrogen-vacancy color centers (red marker) for several laser powers. b Decay rate of Alexa Fluor 555-conjugated versus the excitation power. The fluorescence decreases its intensity at a rate of 0.8 Hz/mW whereas that of the fNDs remained steady. c Fluorescence intensity vs. time illumination of Alexa Fluor 488 and (d) FITC