Tunable Membrane Potential Reconstituted in Giant Vesicles Promotes Permeation of Cationic Peptides at Nanomolar Concentrations.

ABSTRACT: We investigate the influence of membrane potential on the permeation of cationic peptides. Therefore, we employ a microfluidic chip capable of capturing giant unilamellar vesicles (GUVs) in physical traps and fast exchange of chemical compounds. Control experiments with calcein proved that the vesicle membranes' integrity is not affected by the physical traps and applied shear forces. Combined with fluorescence correlation spectroscopy, permeation of fluorescently labeled peptides across vesicle membranes can be measured down to the nanomolar level. With the addition of a lipophilic ruthenium(II) complex Ru(C17)₂²⁺, GUVs consisting of mixed acyl phospholipids are prepared with a negative membrane potential, resembling the membrane asymmetry in cells. The membrane pote

SUBMITTER: Lin CC 

PROVIDER: S-EPMC6420060 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature