title: Efficient multi-site two-photon functional imaging of neuronal circuits.
abstract: Two-photon imaging using high-speed multi-channel detectors is a promising approach for optical recording of cellular membrane dynamics at multiple sites. A main bottleneck of this technique is the limited number of photons captured within a short exposure time (~1ms). Here, we implement temporal gating to improve the two-photon fluorescence yield from holographically projected multiple foci whilst maintaining a biologically safe incident average power. We observed up to 6x improvement in the signal-to-noise ratio (SNR) in Fluorescein and cultured hippocampal neurons showing evoked calcium transients. With improved SNR, we could pave the way to achieving multi-site optical recording of fluorogenic probes with response times in the order of ~1ms.
authors.affiliation: The John Curtin School of Medical Research, Australian National University, Canberra, ACT 2601, Australia.
authors.forename: Michael Lawrence
authors.initials: ML
authors.lastname: Castanares
authors.affiliation: The John Curtin School of Medical Research, Australian National University, Canberra, ACT 2601, Australia.
authors.forename: Vini
authors.initials: V
authors.lastname: Gautam
authors.affiliation: The John Curtin School of Medical Research, Australian National University, Canberra, ACT 2601, Australia.
authors.forename: Jack
authors.initials: J
authors.lastname: Drury
authors.affiliation: Research School of Physics and Engineering, Australian National University, Canberra, ACT 2601, Australia.
authors.forename: Hans
authors.initials: H
authors.lastname: Bachor
authors.affiliation: The John Curtin School of Medical Research, Australian National University, Canberra, ACT 2601, Australia.
authors.forename: Vincent R
authors.initials: VR
authors.lastname: Daria
keywords: (110.0110) Imaging systems; (170.2520) Fluorescence microscopy