[Sci. Rep.] Ca-Mediated Electroformation of Cell-Sized Lipid Vesicles
writer：Fei Tao, Peng Yang*
keywords：Giant Vesicles; Self-Assembly; Calcium; Electroformation; Biomimetic Cell
source：期刊
specific source：Scientific Reports
Issue time：2015年
Cell-sized lipid giant unilamellar vesicles (GUVs) are formed when synthetic or natural lipid molecules self-assemble to construct a single bilayer compartment with similar morphology and size to living cells. The physics of self-assembly process is only generally understood and no mechanism is revealed to strongly affect the overall size, so the size distribution of GUVs tends to be very polydisperse. Herein we report a strategy for the production of controlled size distributions of GUVs by a novel mechanism dissecting the mediation ability of calcium (Ca) on the conventional electroformation of GUVs. We finely construct both of the calcium ion (Ca2+) and calcium carbonate (CaCO3) mineral adsorption layers on lipid film surface respectively during the electroformation of GUVs. It is found that Ca2+ Slip plane polarized by alternating electric field could induce a pattern of electroosmotic flow across the surface, and thus confine the fusion and growth of GUVs so as to facilitate the formation of closely-packed and uniform GUVs. The model is further supported and improved by directly using CaCO3 that is in situ formed on a lipid film surface via a mineralization process, providing a GUV population with good monodispersity. The two models deciphers the new biological function of calcium on the birth of cell-like lipid vesicles, and thus might be potentially relevant to the construction of new model to elucidate the cellular development process.