Membrane Potential-Mediated Vesicle Fusion for DNA Delivery Triggered by Ion Permeation

Area of Science:

• Biochemistry
• Physical Chemistry
• Materials Science

Background:

• Membrane fusion is crucial for biological processes.
• Controlling vesicle fusion is essential for applications like drug delivery.
• Existing methods often lack precise temporal control.

Purpose of the Study:

• To develop a novel method for inducing membrane fusion in giant unilamellar vesicles (GUVs).
• To utilize pH changes as a trigger for controlled vesicle fusion.
• To enable precise control over the timing and environment of fusion events.

Main Methods:

• Adjusting the external solution pH to create a charge imbalance across GUV membranes.
• Utilizing proton and hydroxide ion permeation to alter vesicle surface charge.
• Encapsulating DNA in negatively charged large unilamellar vesicles (LUVs) for electrostatic attraction with protonated GUVs.

Main Results:

• Successfully induced full membrane fusion between GUVs and LUVs by lowering external pH.
• Confirmed fusion via fluorescence of nucleic acid-staining reagents reacting with delivered DNA.
• Demonstrated that pH control effectively triggers and regulates vesicle fusion.

Conclusions:

• pH-induced membrane fusion offers a controllable method for vesicle fusion.
• This technique allows for precise control over fusion timing and postfusion conditions.
• The method has potential applications in controlled delivery systems and synthetic biology.