Water-Soluble Molecular Wires for Membrane Potential Imaging.

Area of Science:

• Biophysics
• Chemical Biology
• Molecular Imaging

Background:

• Voltage-sensitive probes, known as PET molecular wires, are crucial for studying membrane potential.
• Existing probes suffer from poor aqueous solubility, limiting their use in tissue imaging due to toxicity concerns with organic solvents.

Purpose of the Study:

• To synthesize and characterize novel, water-soluble amphiphilic molecular wires.
• To demonstrate the efficacy of these new probes for membrane potential imaging in various biological tissues.

Main Methods:

• Synthesis of molecular wires comprising a rosamine acceptor and a dimethylaniline donor.
• Modification with carboxylates or polyethylene glycol (PEG) groups to enhance water solubility.
• Photophysical characterization and testing in electrically stimulated mouse cardiomyocytes, neurohypophysis, and islets of Langerhans.

Main Results:

• Successful synthesis of water-soluble molecular wires with improved membrane labeling capabilities.
• Demonstrated functional responses in electrically stimulated cardiomyocytes, neurohypophysis, and glucose-stimulated islets of Langerhans.
• Probes exhibit potential for accurate membrane potential imaging in complex biological environments.

Conclusions:

• Developed novel water-soluble molecular wires that overcome previous limitations in tissue imaging.
• These probes represent a valuable advancement for optical reporters of membrane potential.
• The new probes facilitate improved visualization of cellular electrical activity in intact tissues.