Supported bilayer electrophoresis under controlled buffer conditions

Christopher F. Monson, Hudson P. Pace, Chunming Liu, Paul S. Cremer

Research output: Contribution to journalArticlepeer-review

19 Scopus citations

Abstract

A pH controlled flow cell device was constructed to allow electrophoretic movement of charged lipids and membrane associated proteins in supported phospholipid bilayers. The device isolated electrolysis products near the electrodes from the electrophoresis process within the bilayer. This allowed the pH over the bilayer region to remain within ±0.2 pH units or better over many hours at salt concentrations up to 10 mM. Using this setup, it was found that the electrophoretic mobility of a dye conjugated lipid (Texas Red 1,2-dihexadecanoyl-sn-glycero-3-phosphoethanolamine (TR-DHPE)) was essentially constant between pH 3.3 and 9.3. In contrast, streptavidin, which was bound to biotinylated lipids, shifted from migrating cathodically at acidic pH values to migrating anodically under basic conditions. This shift was due to the modulation of the net charge on the protein, which changed the electrophoretic forces experienced by the macromolecule. The addition of a polyethylene glycol (PEG) cushion beneath the bilayer or the increase in the ionic strength of the buffer solution resulted in a decrease of the electroosmotic force experienced by the streptavidin with little effect on the Texas Red-DHPE. As such, it was possible in part to control the electrophoretic and electroosmotic contributions to streptavidin independently of one another.

Original languageEnglish (US)
Pages (from-to)2090-2096
Number of pages7
JournalAnalytical Chemistry
Volume83
Issue number6
DOIs
StatePublished - Mar 15 2011

All Science Journal Classification (ASJC) codes

  • Analytical Chemistry

Fingerprint Dive into the research topics of 'Supported bilayer electrophoresis under controlled buffer conditions'. Together they form a unique fingerprint.

Cite this