Regulating structural and mechanical properties of pectin reinforced liposomes at fluid/solid interface

This work presents the design and study of pectin (PEC) reinforced Egg Lecithin (EPC) liposomes and their structural, mechanical and thermal properties at fluid/solid interface. The liposomes have been analyzed using ATR-FTIR, DSC, SAXS and Quartz crystal microbalance (QCM) with dissipation. An asymmetric melting temperature profile in DSC thermograms with increasing concentration of PEC suggested reduced co-operativity of lipids in the vesicles resulting from different populations of PEC associated lipids. QCM showed PEC stabilized EPC liposome has nearly an order higher mechanical strength compared with EPC as also seen from enhanced heat capacity in DSC. SAXS shows that the PEC locating in the lipid bilayer results in swelling in the non-polar region (similar to 30%) and a reduction in overall bilayer thickness (similar to 6%) compared with that of pure EPC. The nearly equal rotation correlation time tau(r) for EPC (3.25 +/- 0.18 ns) and PEC stabilized liposomes (3.20 +/- 0.2 ns) from fluorescence spectroscopy suggests that PEC in lipid bilayers does not induce any structural deformations. These liposomes visualized by transmission electron microscopy and atomic force microscopy show well-defined morphology. The findings offer a new perspective on understanding the interactions between lipid molecules and biopolymers and may aid in designing stable composite delivery vehicles.

Automated summary

This study investigates the design and properties of pectin-reinforced egg lecithin liposomes, revealing that pectin can enhance mechanical strength and heat capacity, reduce overall bilayer thickness, and maintain structural integrity without deformations.