A Bright Deep-Red AIEgen with Locked Noncoplanar Conformation for Lipid Droplet-Specific Imaging

In the field of fluorescent materials, bright deep-red/near-infrared (DR/NIR) luminogens are always in demand whose rationally and accurately design yet are challenging. Current design strategy of DR/NIR emitters mainly depends on the construction of large p-conjugation and strong donor-acceptor system, which commonly suffers the quenching factors from p-p stacking and twisted intramolecular charge transfer (TICT) effect. In this work, we employed the non-covalent interactions and constructed a luminogen with rigid and twisted conformation, which not only red-shifts the emission wavelength of the luminogen to DR/NIR region but also effectively suppresses the non-radiative decay by p-p stacking and TICT. Moreover, the rational molecular design endows the new luminogen with two-photo absorption capability and superior selectivity towards lipid droplets in different levels including living cells, tissues, and live fish embryo. This work thus presents an elegant, facile and efficient strategy for generating functional DR/NIR emitters.