A ring-flippable sugar as a stimuli-responsive component of liposomes

Area of Science:

• Biomaterials Science
• Drug Delivery Systems
• Supramolecular Chemistry

Background:

• Liposomes are crucial for drug delivery but often lack stimuli-responsiveness.
• Developing smart liposomes that release drugs on demand is a key challenge in pharmaceutical research.

Purpose of the Study:

• To synthesize and characterize novel stimuli-responsive liposomes using 2,4-diaminoxylose (Xyl) derivatives.
• To investigate the structural transformations and drug release capabilities of these Xyl-based liposomes in response to external stimuli.

Main Methods:

• Synthesis of Xyl derivatives (C8Xyl, C16Xyl) with varying alkyl chain lengths.
• Nuclear Magnetic Resonance (NMR) spectroscopy to analyze conformational changes.
• Osmotic pressure and electron microscopy to study liposome formation and structure.
• Fluorophore incorporation to assess drug release dynamics.

Main Results:

• Xyl derivatives undergo conformational switches ((4)C1 to (1)C4 and vice versa) upon addition of Zn(2+) and H+.
• C8Xyl forms aggregates that transform into liposomes upon Zn(2+) addition, while C16Xyl forms liposomes directly.
• Stimuli-responsive drug release was demonstrated, with HCl triggering release from C8Xyl+Zn liposomes.

Conclusions:

• 2,4-diaminoxylose (Xyl) can serve as a stimuli-responsive component in liposome design.
• The synthesized Xyl-based liposomes exhibit tunable structural changes and controlled drug release.
• This research offers a promising platform for developing advanced drug delivery systems.