Fig. 5.

(a) Fluorescence imaging of HeLa cells was performed using 10 μM of probe A incubated in a serum-free medium for varying time intervals. The green channel (channel I) was employed to detect the visible fluorescence of probe A in the range of 425–525 nm, while the red channel (channel II) captured near-infrared fluorescence between 600–675 nm. Green fluorescence was visualized using Alexa Fluor 405 (excitation at 405 nm), and red fluorescence was monitored using Alexa Fluor 568 (excitation at 559 nm). All fluorescence images are presented with a scale bar of 50 μm. (b) Histograms depicting the emission intensities of channel I (green) and channel II (red) (top), and the fluorescence intensity ratio of channel II to channel I for probe A in HeLa cells (bottom) over different time intervals, as quantified from the fluorescence images with SD bars based on n = 3.