Specific Fluorescence Probes for Lipid Droplets Based on Simple AIEgens.

Area of Science:

• Biochemistry
• Cell Biology
• Organic Chemistry

Background:

• Lipid droplets (LDs) are crucial organelles involved in cellular processes and linked to diseases like cancer.
• Accurate localization and concentration monitoring of LDs are vital for biomedical research and healthcare.

Purpose of the Study:

• To develop novel, cost-effective fluorescent probes for specific and sensitive detection of lipid droplets in living cells.
• To investigate the photophysical properties and cellular applications of the synthesized luminogens.

Main Methods:

• Facile synthesis and purification of two luminogens, FAS and DPAS.
• Characterization of aggregation-induced emission (AIE) and excited-state intramolecular proton transfer (ESIPT) properties.
• In vitro and in vivo imaging of lipid droplets in living cells, assessing cytocompatibility and photostability.

Main Results:

• FAS and DPAS exhibit AIE and ESIPT, producing bright orange and yellow emissions in aggregated states.
• The probes show large Stokes shifts and reversible pH-dependent "on-off" fluorescence switching.
• Both probes selectively accumulate in LDs in living cells, providing high contrast and resolution.
• FAS and DPAS demonstrate superior photostability compared to commercial LD probes.

Conclusions:

• FAS and DPAS are highly specific, biocompatible, photostable, and cost-effective probes for LD imaging.
• These probes are promising tools for studying LD-related intracellular activities, including pathology and pharmacology.
• The developed probes offer significant advantages for advancing lipid droplet research.