RT Journal Article ID 48f3e02822658c6c A1 Choudhury, Niloy A1 Zhang, Zhaoqiang A1 Zhao, Feng A1 Gu, Ling A1 Mohanty, Samar T1 Label-free optical detection of optogenetic activation of cells using phase-sensitive Fourier domain optical coherence tomography JF Visualization, Image Processing and Computation in Biomedicine JO VIPCB YR 2012 FD 2012-11-16 VO 1 IS 1 OP 0 K1 Optogenetics K1 Phase-sensitive OCT K1 label fee detection of Channelrhodpsin-2 AB The existing methods for detection of neural activity during optogenetic stimulation are either mechanically intrusive or chemically invasive. Here, we report development of a label-free non-invasive optical readout method to monitor the changes in the cells resulting from optogenetic activation. Phase sensitive Fourier domain optical coherence tomography (PSFD-OCT) was deployed to detect the activation of Channelrhodpsin-2 sensitized cells under the stimulation of blue light. A monolayer of transfected human embryonic kidney cells (HEK 293) in a cell culture dish was activated using a fiber-coupled laser diode that was modulated by a square wave (frequency 30Hz with 50% duty cycle). Using the PSFD-OCT system, we demonstrate measurement of the optical path length change in the cell monolayer because of light-induced activation. PB Begell House LK https://www.dl.begellhouse.com/journals/7e4ff0643eace965,32391aa83c0df898,48f3e02822658c6c.html