Fig. 2. (a–g) TP images of 5.0 μM NCNO-loaded HepG2 cells incubated with various amounts of NOC-9 (0, 5, 10, 20, 30, 40, 50 μM) for 30 min. (h) Relative TP fluorescence intensity in (a)–(g). The two-photon excitation wavelength was 830 nm, and the emission was collected at 600–700 nm. Scale bars, 10 μm.