Molecular Interaction of a New Antibacterial Polymer with a Supported Lipid Bilayer Measured by an in situ Label-Free Optical Technique

International Journal of Molecular Sciences

Robert Horvath¹  Balázs Kobzi²  Helmut Keul³  Martin Moeller³ 

[1] MTA TTK MFA Institute for Technical Physics and Materials Science, Research Centre for Natural Sciences, Budapest, Konkoly Thege u. 29-33 H-1121, Hungary; E-Mail:;Laboratory of Interfaces and Nanostructures, Institute of Chemistry, Eötvös Loránd University, P.O. Box 32, Budapest 112 H-1518, Hungary; E-Mails:;DWI an der RWTH Aachen e.V. and Institute of Technical and Macromolecular Chemistry, RWTH Aachen, Forckenbeckstr. 50, Aachen D-52056, Germany; E-Mail:

关键词: antibacterial polymer;    supported lipid bilayer;    optical waveguide spectroscopy;    optical anisotropy;    label-free measurement;   

DOI  :  10.3390/ijms14059722

来源: mdpi

【 摘 要 】

The interaction of the antibacterial polymer–branched poly(ethylene imine) substituted with quaternary ammonium groups, PEO and alkyl chains, PEI₂₅QI₅J₅A8₁₅–with a solid supported lipid bilayer was investigated using surface sensitive optical waveguide spectroscopy. The analysis of the optogeometrical parameters was extended developing a new composite layer model in which the structural and optical anisotropy of the molecular layers was taken into consideration. Following in situ the change of optical birefringence we were able to determine the composition of the lipid/polymer surface layer as well as the displacement of lipid bilayer by the antibacterial polymer without using additional labeling. Comparative assessment of the data of layer thickness and optical anisotropy helps to reveal the molecular mechanism of antibacterial effect of the polymer investigated.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland