Two-color Emissive AIEgens with Anti-Kasha Property for Dual-Organelle Imaging and Phototherapy

Despite the rapid development of probes for targeting single organelle, construction of robust dual-organelle targeting probes with multicolor emission was rarely reported. Towards this end and in consideration of the unique advantages of aggregation-induced emission luminogens (AIEgens), two dual emissive AIEgens with donor-π-acceptor structures were designed and syn-thesized, namely QT-1 and QF-2. Both two AIEgens exhibited excitation wavelength-dependence defying the Kasha’s rule. The invariant near-infrared emission was originated from S1 of AIEgens to S0. However, its anti-Kasha luminescence at a short wavelength from the S2 state can be tuned by changing the excitation wavelength. Given the two-color emission of AIEgens, QT-1 and QF-2 could stain lipid droplets (LDs) and mitochondria in a blue and red fluorescence, respectively. Moreover, thanks to the near-infrared emission and abundant ROS generation efficiency of QT-1, it was chosen as a photodynamic thera-py agent to selectively kill cancer cells from normal cells. Upon light irradiation, obvious decrease of mitochondrial membrane potential (MMP) and serious change of mitochondrial shape in cells were observed, which corresponded to the efficient inhibi-tion of tumor growth in vivo. This work afforded a promising strategy for the construction of multicolor emission by tuning anti-Kasha behaviors and to expand their application in dual-organelle targeting-based phototheranostics.