Photo-Enhanced Aqueous Solubilization of Azobenzene-Incorporated Lipids

Area of Science:

• Medicinal Chemistry
• Materials Science
• Biotechnology

Background:

• Lipids are vital in biology and medicine but challenging to formulate due to hydrophobicity.
• Developing strategies to improve lipid solubility is crucial for pharmaceutical applications.

Purpose of the Study:

• To enhance the aqueous solubility of lipids using light-responsive molecular design.
• To synthesize and characterize azo-lipids for on-demand solubilization.

Main Methods:

• Incorporation of azobenzene units into fatty acids and phosphatidylcholine to create azo-lipids.
• Utilizing UV (365 nm) and visible light to induce trans-cis isomerization.
• Quantifying solubilization changes using UV-vis spectroscopy and reverse-phase HPLC.

Main Results:

• Synthesized azo-lipids demonstrated reversible photoisomerization upon light exposure.
• Azobenzene-incorporated phosphatidylcholine 2 showed a 496-fold increase in solubilization after UV irradiation (2.030 to 1008 µM).
• Improved solubility is attributed to photoisomerization-induced molecular bending and reduced intermolecular interactions.

Conclusions:

• Light-responsive azo-lipids offer a novel strategy for on-demand aqueous solubilization of hydrophobic compounds.
• This approach can improve the handling, storage, and therapeutic administration of lipid-based formulations.
• Molecular design incorporating photoisomerizable units presents a promising avenue for overcoming formulation challenges in lipid-based drug delivery.