Fig. 4

Cellular fluorescence properties and cytotoxicity. A, B The fluorescence study of the freeICG/nanoICG in LO2 cells. C, D The fluorescence study of the freeICG/nanoICG in Hepa1-6 cells. E, F The fluorescence study of the freeICG/nanoICG in HepG2 cells. G–I CCK-8 of the freeICG and nanoICG in LO2 (G), Hepa1-6 (H) and HepG2 (I) cells. Data represent mean ± SD, n = 3. *** p < 0.001, Student’s t-test