Polymorphic phase behavior of perfluoroalkylated phosphatidylcholines

Area of Science:

• Materials Science
• Biochemistry
• Physical Chemistry

Background:

• Phosphatidylcholines are key components of biological membranes.
• Fluorinated lipids offer unique physicochemical properties.
• Understanding lipid self-assembly is crucial for biomaterials development.

Purpose of the Study:

• Investigate the polymorphic phase behavior of F-alkyl modified phosphatidylcholines (FnCmPC).
• Characterize the physicochemical properties of FnCmPC aqueous dispersions.
• Assess the stability and membrane properties of FnCmPC-based liposomes.

Main Methods:

• Synthesis of FnCmPC lipids with varying fluorinated (Fn) and hydrocarbon (Cm) chain lengths.
• X-ray diffraction to determine phase behavior (liposomes, ribbon-like, lamellar phases).
• Differential scanning calorimetry to study gel to fluid phase transitions.
• Paramagnetic probe partitioning to assess membrane lipophilicity.

Main Results:

• FnCmPC lipids form stable liposomes, ribbon-like phases, and lamellar phases depending on chain length and temperature.
• FnCmPC liposomes exhibit exceptional stability compared to traditional DPPC vesicles, attributed to perfluoroalkyl tails.
• Gel to fluid phase transition temperature correlates with hydrophobic chain length, particularly the perfluoroalkyl tail.
• Increased fluorophilic character decreases membrane lipophilicity, evidenced by reduced probe solubility.

Conclusions:

• FnCmPC lipids offer tunable self-assembly into stable supramolecular structures like liposomes.
• The perfluoroalkyl tails significantly enhance liposome stability and alter membrane properties.
• These fluorinated lipids present promising candidates for advanced biomaterials and drug delivery systems.