Open AccessLabel-free optical detection of action potential in mammalian neurons
Author(s) -
Subrata Batabyal,
Sarmishtha Satpathy,
Loan Bui,
Young Tae Kim,
Samarendra Mohanty,
Robert Bachoo,
Digant P. Davé
Publication year - 2017
Publication title -
biomedical optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.362
H-Index - 86
ISSN - 2156-7085
DOI - 10.1364/boe.8.003700
Subject(s) - optical recording , tetrodotoxin , membrane potential , optics , optical mapping , biophysics , signal (programming language) , pulse (music) , optical path length , electrophysiology , materials science , neuroscience , physics , biology , computer science , detector , genetics , programming language
We describe an optical technique for label-free detection of the action potential in cultured mammalian neurons. Induced morphological changes due to action potential propagation in neurons are optically interrogated with a phase sensitive interferometric technique. Optical recordings composed of signal pulses mirror the electrical spike train activity of individual neurons in a network. The optical pulses are transient nanoscale oscillatory changes in the optical path length of varying peak magnitude and temporal width. Exogenous application of glutamate to cortical neuronal cultures produced coincident increase in the electrical and optical activity; both were blocked by application of a Na-channel blocker, Tetrodotoxin. The observed transient change in optical path length in a single optical pulse is primarily due to physical fluctuations of the neuronal cell membrane mediated by a yet unknown electromechanical transduction phenomenon. Our analysis suggests a traveling surface wave in the neuronal cell membrane is responsible for the measured optical signal pulses.