RT Journal Article SR Electronic T1 Electro-plasmonic nanoantenna: A nonfluorescent optical probe for ultrasensitive label-free detection of electrophysiological signals JF Science Advances JO Sci Adv FD American Association for the Advancement of Science SP eaav9786 DO 10.1126/sciadv.aav9786 VO 5 IS 10 A1 Habib, Ahsan A1 Zhu, Xiangchao A1 Can, Uryan I. A1 McLanahan, Maverick L. A1 Zorlutuna, Pinar A1 Yanik, Ahmet A. YR 2019 UL http://advances.sciencemag.org/content/5/10/eaav9786.abstract AB Harnessing the unprecedented spatiotemporal resolution capability of light to detect electrophysiological signals has been the goal of scientists for nearly 50 years. Yet, progress toward that goal remains elusive due to lack of electro-optic translators that can efficiently convert electrical activity to high photon count optical signals. Here, we introduce an ultrasensitive and extremely bright nanoscale electric-field probe overcoming the low photon count limitations of existing optical field reporters. Our electro-plasmonic nanoantennas with drastically enhanced cross sections (~104 nm2 compared to typical values of ~10−2 nm2 for voltage-sensitive fluorescence dyes and ~1 nm2 for quantum dots) offer reliable detection of local electric-field dynamics with remarkably high sensitivities and signal–to–shot noise ratios (~60 to 220) from diffraction-limited spots. In our electro-optics experiments, we demonstrate high-temporal resolution electric-field measurements at kilohertz frequencies and achieved label-free optical recording of network-level electrogenic activity of cardiomyocyte cells with low-intensity light (11 mW/mm2).