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arXiv · 1501.00044

Widefield two-photon excitation without scanning: live cell microscopy with high time resolution and low photo-bleaching

Rumelo Amor·Johanna Trägårdh·Gillian Robb·Louise Wilson·Nor Zaihana Abdul Rahman·John Dempster·William Bradshaw Amos·Trevor J. Bushell·Gail McConnell
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Abstract

We demonstrate fluorescence imaging by two-photon excitation without scanning in biological specimens as previously described by Hwang and co-workers, but with an increased field size and with framing rates of up to 100 Hz. During recordings of synaptically-driven Ca$^{2+}$ events in primary rat neurone cultures loaded with the fluorescent Ca$^{2+}$ indicator Fluo-4 AM, we have observed greatly reduced photo-bleaching in comparison with single-photon excitation. This method, which requires no costly additions to the microscope, promises to be useful for work where high time-resolution is required.

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Rumelo Amor, Johanna Trägårdh, Gillian Robb, Louise Wilson, Nor Zaihana Abdul Rahman, John Dempster, William Bradshaw Amos, Trevor J. Bushell, Gail McConnell. 2014-12-30. Widefield two-photon excitation without scanning: live cell microscopy with high time resolution and low photo-bleaching. https://arxiv.org/abs/1501.00044

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