Fusion and molecular aspects of liposomal nanocarriers incorporated with isoprenoids

The present study was conducted to investigate whether typical isoprenyl compounds (TICs) can control liposomal fusion reactions through changes in the physical properties of membranes. The fusion capabilities of TIC-incorporated liposomes were characterized by measuring the ¹³C spin-lattice relaxation times (¹³CT₁) and the gel permeation chromatogram (GPC) patterns. The ¹³CT₁ relaxivities of some of these TIC-liposomes were remarkably enhanced at 27°C. The highest ¹³CT₁ value obtained was for the β-carotene-liposome, which ruptured, and was attributed to the highest membrane fusion reactivity. The other TIC-liposomes incorporated with α-tocopherol, canthaxanthin, or coenzyme Q₁₀ also induced significant fusion and did not rupture in comparison with the β-carotene-liposome. These results show that the incorporations of TICs into lipid bilayers are useful to control liposomal nanocarriers for suitable membrane packing and advantageous phase separation, which could affect membrane-related processes.