Infrared scanning near-field optical microscopy investigates order and clusters in model membranes.
Due to its surface sensitivity and high spatial resolution, scanning near-field optical microscopy (SNOM) has a significant potential to study the lateral organization of membrane domains and clusters. Compared to other techniques, infrared near-field microscopy in the spectroscopic mode has the advantage to be sensitive to specific chemical bonds. In fact, spectroscopic SNOM in the infrared spectral range (IR-SNOM) reveals the chemical content of the sample with a lateral resolution around 100 nm (Cricenti et al., 1998a, 1998b, 2003). Model lipid membranes were studied by IR-SNOM at several wavelengths. Topographical micrographs reveal the presence of islands at the surface and the optical images indicate the formation of locally ordered multiple bilayers - both critically important features for biotechnology and medical applications.
Generosi
J
J
Institut de physique appliquée, Ecole Polytechnique Fédérale, CH-1015 Lausanne, Switzerland. johanna.generosi@epfl.ch
Margaritondo
G
G
Sanghera
J S
JS
Aggarwal
I D
ID
Tolk
N H
NH
Piston
D W
DW
Castellano
A Congiu
AC
Cricenti
A
A
D008051:Lipid Bilayers / Q000737:chemistry; D008563:Membrane Lipids / Q000737:chemistry*; D018613:Microscopy, Confocal / Q000295:instrumentation / Q000379:methods*; D008954:Models, Biological; D010713:Phosphatidylcholines / Q000737:chemistry; D013055:Spectrophotometry, Infrared / Q000295:instrumentation / Q000379:methods*
D008051:Lipid Bilayers; D008563:Membrane Lipids; D010713:Phosphatidylcholines; C017251:1,2-oleoylphosphatidylcholine