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Quantitative imaging of molecular order in lipid membranes using two-photon fluorescence polarimetry.

ABSTRACT: We present a polarimetric two-photon microscopy technique to quantitatively image the local static molecular orientational behavior in lipid and cell membranes. This approach, based on a tunable excitation polarization state complemented by a polarized readout, is easily implementable and does not require hypotheses on the molecular angular distribution such as its mean orientation, which is a main limitation in traditional fluorescence anisotropy measurements. The method is applied to the investigation of the molecular angular distribution in giant unilamellar vesicles formed by liquid-ordered and liquid-disordered micro-domains, and in COS-7 cell membranes. The highest order contrast between ordered and disordered domains is obtained for dyes locating within the membrane acyl chains.

SUBMITTER: Gasecka A

PROVIDER: S-EPMC2776251 | biostudies-literature | 2009 Nov

REPOSITORIES: biostudies-literature

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Quantitative imaging of molecular order in lipid membranes using two-photon fluorescence polarimetry.

Gasecka Alicja A Han Tsai-Jung TJ Favard Cyril C Cho Bong Rae BR Brasselet Sophie S

Biophysical journal 20091101 10

We present a polarimetric two-photon microscopy technique to quantitatively image the local static molecular orientational behavior in lipid and cell membranes. This approach, based on a tunable excitation polarization state complemented by a polarized readout, is easily implementable and does not require hypotheses on the molecular angular distribution such as its mean orientation, which is a main limitation in traditional fluorescence anisotropy measurements. The method is applied to the inves ...[more]

PMID: 19917241

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