Ros-responsive nano-platform for lipid-specific fluorescence imaging of atherosclerosis

Fluorescent probes that specifically targeting Lipid droplets (LDs) have shown potential in biological imaging. Albeit, their in vivo applications are limited due to the hydrophobicity, low signal-to-noise ratio (SNR) and LDs-specificity. Thus, we designed a novel probe namely MeOND, and a reactive oxygen species (ROS)-responsive nano-platform to improve in vivo LDs-specific imaging. MeOND exhibits a remarkable twisted intramolecular charge transfer (TICT) effect with a strongly enhanced near-infrared emission in low-polarity lipid environment. Also, MeOND demonstrates satisfactory biocompatibility and superior intracellular LDs imaging capabilities. MeOND encapsulated nano-platform (MeOND@PMM) presented favorable water solubility and biocompatibility. MeOND@PMM remains stable in physiological conditions but quickly degrades in the environment of elevated ROS level. The released MeOND could then light up the intracellular LDs in atherosclerotic plaques. The design of the probe and nano-platform is expected to provide a better tool for the scientific research of LDs and LDs-related diseases.