(a) Schematic illustration of FL-“dual-quenched” Cy5.5-CBT-NPs preparation and cartoon representation of using Cy5.5-CBT-NPs to image the tumoricidal activity of cytotoxic
T lymphocytes. (b) FL spectra of Cy5.5-CBT (10 μM,
black), Cy5.5-CBT-NPs (5 μM, red), and Cy5.5-CBT-NPs (5 μM) treated with 20 pM GraB (blue) or 20 pM GraB + 100
μM GraB inhibitor (green) in tris(hydroxymethyl)aminomethane
(Tris, 100 mM, pH 7.5) buffer for 4 h, λex = 675
nm, λem = 702 nm. (c) In vivo real-time
FLI of B16-OVA tumor-bearing mice pretreated with saline (Control)
or BEC (BEC treatment) for 3 days followed by intratumoral injection
of 0.78 mg kg–1Cy5.5-CBT-NPs. (d)
Quantification of FL signals in (c). ***P < 0.001.
Reproduced with permission from ref (41). Copyright 2022 American Chemical Society.