Fig. 5.

Optical imaging and MRI results of CNs discussed in the review. (a) Fluorescence images of HepG2 cells and tumor-bearing mice treated with GQDs of different emission wavelengths. Reproduced with permission from Ref. [131] (Copyright 2020, Elsevier). (b) NIR fluorescence images of the cerebrovasculature of mice treated with semiconductor SWCNTs. Reproduced with permission from Ref. [134] (Copyright 2015, Wiley). (c) Raman images of HepG2 cells incubated with SWCNT/Ag/AuNPs nanoprobe at different oxygen levels. Reproduced with permission from Ref. [138] (Copyright 2019, American Chemical Society) (d) MRI of MCF-7 ​cells and tumor-bearing mice treated with DOX/NGR-SWCNT/Gd-DTPA. Reproduced with permission from Ref. [141] (Copyright 2016, Taylor & Francis Group). Note: C, control group; D, Gd-DTPA; B, DOX/NGR-SWCNTs/Gd-DTPA. (e) MRI of H22 tumor-bearing nude mice treated with GO-PEG-γ-Fe₂O₃-DOX. The histogram demonstrates the temporal T₂ signal of the tumor site acquired by region-of-interest (ROI) analysis. Reproduced with permission from Ref. [145] (Copyright 2018, Elsevier).