Unilamellar Characteristic Analysis of 1,2-dioleoyl-sn-3-phosphocholine Liposome of Various Sizes via Atomic Force Microscopy and Patch-Clamp

DOPC liposome properties of various sizes were analyzed via atomic force microscopy (AFM) and patch-clamp. The unilamellarity of small DOPC liposome (below 1 μm) was confirmed via Cryogenic transmission electron microscopy (Cryo-TEM). Small DOPC liposome (below 1 μm) showed a bending modulus (kbend) ranging (between 10−18 and 10−20 J). The bending modulus value was a size dependence. In order words, it decreased as DOPC liposome size increased. For DOPC liposome (above 1 μm), patch-clamp was used to achieve electrically tight whole-cell configurations. Our result showed that the unilamellar DOPC liposome (above 1 μm) exhibit RC circuit response property. It was similar to theoretical values (τ = 4.52 ms) of the unilamellar liposome. In this study, the uniform lamellarity of the DOPC liposome of various sizes was confirmed through electrical and mechanical properties of DOPC liposome.