Fig. 4: Design and characterizations of ONOO–-responsive TTA nanomicelles (TTA-NMs).
From: Molecular near-infrared triplet-triplet annihilation upconversion with eigen oxygen immunity
a Schematic illustration of building ONOO–-responsive TTA-NMs with quenched upconversion via surface-attached Cy7 acceptor. b Transmission electron microscopy (TEM) of TTA-NMs in PBS buffer, scale bar is 100 nm, all experiments were independently repeated three times, yielding similar results. c The corresponding histograms of nanomicelle sizes obtained from analyzing TEM images (~100 particles). d Upconversion emission spectra of the TTA-NMs (5 mg/mL), and TTA-NMs treated with Cy7 and Cy7/ONOO– (30 μM) in PBS buffer (λex = 808 nm, 10 W/cm2). e Upconversion emission stability of TTA-NMs in PBS buffer upon intermittent irradiation of 808-nm laser (spectra were measured after continuous laser exposure of 100 mW/cm2 for two hours each day). Luminescence intensities are presented as mean ± standard deviations (SD) (n = 3). f Confocal laser scanning microscopy (CLSM) images of HeLa cells incubated with TTA-NMs for 0.5, 1, and 1.5 h at 37 °C, scale bar is 75 μm; three independent experiments were repeated, yielding similar results.
