Recent advance of lipid droplets fluorescence imaging with aggregation-induced emission luminogens (AIEgens)

As reservoirs of neutral lipids for energy storage to drive energy-demanding processes, lipid droplets (LDs) play an important role in regulating numerous cellular functions. In addition, LDs are crucial in the progression of some diseases, such as cancer, atherosclerosis, fatty liver disease, hyperlipidemia, diabetes, and neurodegeneration. In clinical diagnosis and biomedical research, fluorescence bioimaging of LDs for the dynamic localization and real-time analysis is commonly utilized. The aggregation-induced emission luminogens (AIEgens) are promising candidates for LD imaging owing to their high signal-to-noise (S/N) ratio, lit up character, excellent photostability, and good biocompatibility. In this review, the design principles and various kinds of AIEgens (reactive AIEgens, red/NIR emission AIEgens, two-photon AIEgens, AIE + ESIPT based luminogens, organoboron materials and other AIEgens) for LDs imaging, LDs dynamic detection, and imaging of other lipidrich organisms are summarized. We anticipate that this review can stimulate further expanding more AIEgens for LDs imaging and detection.

Automated summary

Lipid droplets (LDs) are important reservoirs of neutral lipids for energy storage and play a crucial role in regulating cellular functions and disease progression. Fluorescence bioimaging of LDs is commonly used in clinical diagnosis and biomedical research. Aggregation-induced emission luminogens (AIEgens) show great promise for LD imaging due to their high signal-to-noise ratio and excellent biocompatibility. This review summarizes the design principles and various types of AIEgens for LD imaging as well as imaging of other lipid-rich organisms.