Supralinear scaling behavior of ionic transport in membrane nanochannels regulated by outer-surface charges.

ABSTRACT: The peculiarity of ion transport at the nanoscale is revealed through electrophysiological studies of two biological ion channels: the cation-selective bacterial porin-OmpF and the mitochondrial voltage-dependent anion channel (VDAC). We provide evidence of an unprecedented scaling behavior in the power-law relationship between conductivity and concentration G ∼ c ^α with α > 1 when functional groups attached to the pore inner wall have opposite charges to those located in the nanochannel's outer surface. Indeed, we find α ∼ 1.4 both for OmpF in positively charged membranes and for VDAC in negatively charged ones. The experiments are analyzed using different levels of theoretical models, starting with an equivalent circuit where total electrical

SUBMITTER: Alvero-Gonzalez LM 

PROVIDER: S-EPMC11515935 | biostudies-literature | 2024 Oct

REPOSITORIES: biostudies-literature