Figure 5.

MXene‐based photothermal therapy. a) Absorbance spectra of well‐dispersed aqueous Nb₂C NSs at varied concentrations. b) Photostability profiles of an aqueous Nb₂C NSs solution in NIR‐I and NIR‐II biowindows for five laser on/off cycles. c) Relative viabilities of 4T1 cell line after Nb₂C‐PVP‐induced (40 µg mL⁻¹) photothermal eradication at various power densities (0, 0.5, 1.0, 1.5, and 2 W cm⁻²) of laser (n = 5, mean ± SD). d) Temperature elevations of Nb₂C NSs‐dispersed aqueous suspensions upon exposure to tissue‐penetrating NIR‐I and NIR‐II laser via photothermal conversion. e) Schematic diagram of in vivo tumor tissue penetration for photothermal conversion based on NIR‐I and NIR‐II. f) Cancer cellular proliferation at varied depths of tumor tissues by antigen Ki‐67 immunofluorescence staining (scale bar: 50 µm). g) Scheme of synthetic procedure and in vivo photothermal tumor ablation process of 2D biodegradable Nb₂C (modified with PVP). h) Time‐dependent tumor growth curves after various treatments. Reproduced with permission.49 Copyright 2017, American Chemical Society.