A red-emitting indolium fluorescence probe for membranes - flavonoids interactions

Area of Science:

• Biophysical Chemistry
• Materials Science
• Pharmacology

Background:

• Developing sensitive probes for membrane interactions is crucial for understanding drug delivery and biological processes.
• Indolium derivatives offer potential as fluorescent probes due to their tunable optical properties.

Purpose of the Study:

• To develop and characterize a red-emitting indolium derivative (H3) as a sensitive membrane fluorescence probe.
• To investigate the probe's ability to monitor flavonoid-membrane interactions and assess drug bio-affinities.

Main Methods:

• Synthesis and characterization of the indolium derivative (H3).
• Liposome preparation and probe encapsulation studies.
• Fluorescence spectroscopy to monitor probe behavior and flavonoid interactions.
• ζ-potential and particle size measurements for membrane embedding confirmation.

Main Results:

• The indolium derivative (H3) exhibited enhanced fluorescence upon binding to liposome interfaces.
• Ultrasonic treatment facilitated probe penetration into lipid bilayers with high encapsulation efficiency (71.4%).
• Quercetin rapidly dissociated the probe from liposomes, indicating strong flavonoid-membrane interaction.

Conclusions:

• The indolium derivative (H3) is a sensitive and effective membrane fluorescence probe.
• The probe successfully monitored flavonoid binding affinities to membranes, correlating with antioxidant activities.
• This probe shows promise for studying drug bio-affinities and membrane interactions in biological systems.