Mapping surface charge density of lipid bilayers by quantitative surface conductivity microscopy

Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaperJournal articleResearchpeer-review

98 Citations (Scopus)

Abstract

Local surface charge density of lipid membranes influences membrane-protein interactions leading to distinct functions in all living cells, and it is a vital parameter in understanding membrane-binding mechanisms, liposome design and drug delivery. Despite the significance, no method has so far been capable of mapping surface charge densities under physiologically relevant conditions. Here, we use a scanning nanopipette setup (scanning ion-conductance microscope) combined with a novel algorithm to investigate the surface conductivity near supported lipid bilayers, and we present a new approach, quantitative surface conductivity microscopy (QSCM), capable of mapping surface charge density with high-quantitative precision and nanoscale resolution. The method is validated through an extensive theoretical analysis of the ionic current at the nanopipette tip, and we demonstrate the capacity of QSCM by mapping the surface charge density of model cationic, anionic and zwitterionic lipids with results accurately matching theoretical values.

Original languageEnglish
Article number12447 (2016)
JournalNature Communications
Volume7
ISSN2041-1723
DOIs
Publication statusPublished - 26 Aug 2016

Fingerprint

Dive into the research topics of 'Mapping surface charge density of lipid bilayers by quantitative surface conductivity microscopy'. Together they form a unique fingerprint.

Cite this