Selective Dual-Channel Imaging on Cyanostyryl-Modified Azulene Systems with Unimolecularly Tunable Visible–Near Infrared Luminescence

摘要

Although organic light-emitting molecules have received a growing attention and applicability in modern bioimaging science, the design and control of complex photoluminescent properties in unimolecularly selective imaging remains a challenging topic. Considering that tunable multipathway imaging can be advantagedly connected with treatment processes in therapy, the integration of an azulene and a cyanostyryl moiety into one skeleton is carried out for the generation of in situ stimuliresponsive luminescent materials, with the aim to achieve tunable and effective emissions in distinct channels through smart molecular design on a single-molecular platform. This strategy takes advantage of 1) the Z/E isomerization of the cyanostyryl unit that can vary the push– pull effect of the substitution on azulene, accompanied by altering absorption and emission of individual excited states, and 2) an optimized excited-state regulation for opening a near infrared emissive channel and making up for a controllable dual-pathway luminescent system together with the utilization of visible emission. As exemplified by a demonstration of manipulating the luminescence at the cell level, the materials exhibit a superior application potential for unimolecularly selective imaging, labeling and probing events.