Combined QCM-D and EIS study of supported lipid bilayer formation and interaction with pore-forming peptides
Artikel i vetenskaplig tidskrift, 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

Författare

Elisabeth Briand

Chalmers, Teknisk fysik, Biologisk fysik

Michael Zäch

Chalmers, Teknisk fysik, Kemisk fysik

Sofia Svedhem

Chalmers, Teknisk fysik, Biologisk fysik

Bengt Herbert Kasemo

Chalmers, Teknisk fysik, Kemisk fysik

Sarunas Petronis

Chalmers, Teknisk fysik, Biologisk fysik

The Analyst

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

Vol. 135 2 343-350

Styrkeområden

Nanovetenskap och nanoteknik

Livsvetenskaper och teknik

Materialvetenskap

Ämneskategorier

Annan fysik

DOI

10.1039/b918288h