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 degrees C. The highest 13CT1 value obtained was for the beta-carotene-liposome, which ruptured, and was attributed to the highest membrane fusion reactivity. The other TIC-liposomes incorporated with alpha-tocopherol, canthaxanthin, or coenzyme Q10 also induced significant fusion and did not rupture in comparison with the beta-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.