Fig. 2. Energy transfer involved photophysical behavior of nanogels.
a Spectra overlap between the emission of the DTMMA (donor) and absorption of the SPMA (open and closed form, acceptor); b Schematic illustration of HOMO and LUMO isosurfaces of DTMMA and SPMA with their first singlet excitation energies in a non-polar environment based on DFT and TD-DFT calculations; c, d Emission intensity changes of nanogel N4 before and after UV irradiation for 0–100 s (λex. = 410 nm, slit width: Ex. = 1 nm, Em. = 1 nm); e Fluorescence intensity cycling upon UV and vis irradiation (the DTM channel was recorded at 520 nm and the SP channel was recorded at 610 nm, irradiation time: 120 s); f Fluorescence images of the light-switchable nanogel solutions (N1–5) before and after UV irradiation for 120 s. Related data are provided in Source data file.