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Label-free imaging of membrane potential using membrane electromotility.

ABSTRACT: Electrical activity may cause observable changes in a cell's structure in the absence of exogenous reporter molecules. In this work, we report a low-coherence interferometric microscopy technique that can detect an optical signal correlated with the membrane potential changes in individual mammalian cells without exogenous labels. By measuring milliradian-scale phase shifts in the transmitted light, we can detect changes in the cells' membrane potential. We find that the observed optical signals are due to membrane electromotility, which causes the cells to deform in response to the membrane potential changes. We demonstrate wide-field imaging of the propagation of electrical stimuli in gap-junction-coupled cell networks. Membrane electromotility-induced cell deformation may be useful as a reporter of electrical activity.

SUBMITTER: Oh S

PROVIDER: S-EPMC3388206 | biostudies-literature | 2012 Jul

REPOSITORIES: biostudies-literature

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Label-free imaging of membrane potential using membrane electromotility.

Oh Seungeun S Fang-Yen Christopher C Choi Wonshik W Yaqoob Zahid Z Fu Dan D Park YongKeun Y Dassari Ramachandra R RR Feld Michael S MS

Biophysical journal 20120701 1

Electrical activity may cause observable changes in a cell's structure in the absence of exogenous reporter molecules. In this work, we report a low-coherence interferometric microscopy technique that can detect an optical signal correlated with the membrane potential changes in individual mammalian cells without exogenous labels. By measuring milliradian-scale phase shifts in the transmitted light, we can detect changes in the cells' membrane potential. We find that the observed optical signals ...[more]

PMID: 22828327

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Dataset Information

Label-free imaging of membrane potential using membrane electromotility.

Publications

Label-free imaging of membrane potential using membrane electromotility.

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