Fig. 6: Quantitative sensing in live cells and dual-emission imaging in vivo.
Dual-channel and ratiometric imaging of QSG-7701 cells (a–d, pretreated with various concentrations of GSH); A549 and Hep-G2 cells incubated with DCM-IFC-4 (30 µM) and either untreated (e, g) or treated with (f, h) NEM (a derivatization agent which covalently sequesters GSH). Note: The green channel was 520 ± 20 nm, the red channel was 700 ± 20 nm, and ratiometric images were generated from the 520 and 700 nm channels, λex = 488 nm. i Dual-channel response with internal reference signal in cells. Data with error bars are expressed as mean ± s.d., n = 3. Source data are provided as a Source Data file. j Standard curve of the I520 nm: I700 nm ratio as a function of GSH concentration. Data with error bars are expressed as mean ± s.d., n = 3. Source data are provided as a Source Data file. k Ratio value in A549 and Hep-G2 cells with and without NEM. Data with error bars are expressed as mean ± s.d., n = 3. Source data are provided as a Source Data file. (l, m) In vivo dual-channel fluorescence imaging of xenograft tumor (A549 cell) bearing mice at various times (0.5, 2, 4, 6, 12, 24 h) after the intravenous injection of DCM-IFC-4 (2.44 mg kg−1), the tumor site is circled in red. n, o Ex vivo dual-channel fluorescence imaging of the excised organs (tumor, heart, liver, spleen, lung, and kidney) at 24 h after the intravenous injection of DCM-IFC-4. Note: fluorescence signals at 600 nm (rainbow scale) and 700 nm (yellow-red scale).
