Combined QCM-D and EIS study of supported lipid bilayer formation and interaction with pore-forming peptides
Journal article, 2010

A novel set-up combining the quartz crystal microbalance with dissipation monitoring technique (QCM-D) and electrochemical impedance spectroscopy (EIS) under flow conditions was successfully used to follow supported lipid bilayer (SLB) formation on SiO(2). This study demonstrates the simultaneous detection, in real time, of both the electrical and the structural properties of the SLB. The combination of the two techniques provided novel insights regarding the mechanism of SLB formation: we found indications for an annealing process of the lipid alkyl chains after the mass corresponding to complete bilayer coverage had been deposited. Moreover, the interaction of the SLB with the pore-forming toxin, gramicidin D (grD) was studied for grD concentrations ranging from 0.05 to 40 mg L(-1). Membrane properties were altered depending on the toxin concentration. For low grD concentrations, the electrical properties of the SLB changed upon insertion of active ion channels. For higher concentrations, the QCM-D data showed dramatic changes in the viscoelastic properties of the membrane while the EIS spectra did not change. AFM confirmed significant structural changes of the membrane at higher grD concentrations. Thus, the application of combined QCM-D and EIS detection provides complementary information about the system under study. This information will be particularly important for the continued detailed investigation of interactions at model membrane surfaces

Author

Elisabeth Briand

Chalmers, Applied Physics, Biological Physics

Michael Zäch

Chalmers, Applied Physics, Chemical Physics

Sofia Svedhem

Chalmers, Applied Physics, Biological Physics

Bengt Herbert Kasemo

Chalmers, Applied Physics, Chemical Physics

Sarunas Petronis

Chalmers, Applied Physics, Biological Physics

The Analyst

0003-2654 (ISSN) 1364-5528 (eISSN)

Vol. 135 2 343-350

Areas of Advance

Nanoscience and Nanotechnology (2010-2017)

Life Science Engineering (2010-2018)

Materials Science

Subject Categories

Other Physics Topics

DOI

10.1039/b918288h

More information

Created

10/7/2017