CAPRYDAA, an anthracene dye analog to LAURDAN: a comparative study using cuvette and microscopy

Area of Science:

• Biophysics
• Chemical Biology
• Materials Science

Background:

• Molecular probes are crucial for visualizing cellular structures and dynamics.
• Existing probes like LAURDAN have limitations, often requiring UV or specialized excitation.
• Solvatochromic probes offer sensitivity to environmental polarity, useful for membrane studies.

Purpose of the Study:

• To synthesize and characterize a novel anthracene derivative, CAPRYDAA, as a molecular probe for membrane dynamics.
• To evaluate CAPRYDAA's photophysical properties and its performance compared to LAURDAN.
• To demonstrate CAPRYDAA's utility in discriminating lipid phases and heterogeneity in cellular membranes.

Main Methods:

• Synthesis of 2-nonanoyl-6-(dimethylamino)anthracene (CAPRYDAA).
• Photophysical characterization in homogeneous media, synthetic bilayers, and live cells.
• Fluorescence microscopy using one-photon (488 nm) and two-photon excitation.
• Assessment of lipid phase discrimination in giant unilamellar vesicles (GUVs) and cells.

Main Results:

• CAPRYDAA exhibits solvatochromic properties with red-shifted absorption and emission due to its structure.
• Its photophysical behavior is comparable to LAURDAN but excitable with visible light (488 nm).
• CAPRYDAA effectively discriminates lipid phases and liquid-liquid heterogeneity in GUVs and cells.
• The probe is compatible with both one-photon and two-photon excitation, allowing co-localization studies.

Conclusions:

• CAPRYDAA is a versatile molecular probe for studying membrane dynamics and supramolecular organization.
• Its excitation with visible light simplifies imaging protocols, enabling use with standard confocal microscopes.
• CAPRYDAA offers an improved alternative to existing probes for detailed membrane analysis.