title: Electric Field Modulation of Semiconductor Quantum Dot Photoluminescence: Insights Into the Design of Robust Voltage-Sensitive Cellular Imaging Probes.
abstract: The intrinsic properties of quantum dots (QDs) and the growing ability to interface them controllably with living cells has far-reaching potential applications in probing cellular processes such as membrane action potential. We demonstrate that an electric field typical of those found in neuronal membranes results in suppression of the QD photoluminescence (PL) and, for the first time, that QD PL is able to track the action potential profile of a firing neuron with millisecond time resolution. This effect is shown to be connected with electric-field-driven QD ionization and consequent QD PL quenching, in contradiction with conventional wisdom that suppression of the QD PL is attributable to the quantum confined Stark effect.
authors.affiliation: Center for Bio/Molecular Science and Engineering, Naval Research Laboratory , Code 6900, 4555 Overlook Avenue SW, Washington, DC 20375, United States.
authors.forename: Clare E
authors.initials: CE
authors.lastname: Rowland
authors.affiliation: Optical Sciences Division, Naval Research Laboratory , Code 5600, 4555 Overlook Avenue SW, Washington, DC 20375, United States.
authors.forename: Kimihiro
authors.initials: K
authors.lastname: Susumu
authors.affiliation: Optical Sciences Division, Naval Research Laboratory , Code 5600, 4555 Overlook Avenue SW, Washington, DC 20375, United States.
authors.forename: Michael H
authors.initials: MH
authors.lastname: Stewart
authors.affiliation: Optical Sciences Division, Naval Research Laboratory , Code 5600, 4555 Overlook Avenue SW, Washington, DC 20375, United States.
authors.forename: Eunkeu
authors.initials: E
authors.lastname: Oh
authors.affiliation: Optical Sciences Division, Naval Research Laboratory , Code 5600, 4555 Overlook Avenue SW, Washington, DC 20375, United States.
authors.forename: Antti J
authors.initials: AJ
authors.lastname: Mäkinen
authors.affiliation: Materials Science and Technology Division, Naval Research Laboratory , Code 6300, 4555 Overlook Avenue SW, Washington, DC 20375, United States.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: O'Shaughnessy
authors.affiliation: Optical Sciences Division, Naval Research Laboratory , Code 5600, 4555 Overlook Avenue SW, Washington, DC 20375, United States.
authors.forename: Gary
authors.initials: G
authors.lastname: Kushto
authors.affiliation: Optical Sciences Division, Naval Research Laboratory , Code 5600, 4555 Overlook Avenue SW, Washington, DC 20375, United States.
authors.forename: Mason A
authors.initials: MA
authors.lastname: Wolak
authors.affiliation: Center for Bio/Molecular Science and Engineering, Naval Research Laboratory , Code 6900, 4555 Overlook Avenue SW, Washington, DC 20375, United States.
authors.forename: Jeffrey S
authors.initials: JS
authors.lastname: Erickson
authors.affiliation: Materials Science and Technology Division, Naval Research Laboratory , Code 6300, 4555 Overlook Avenue SW, Washington, DC 20375, United States.
authors.forename: Alexander L
authors.initials: AL
authors.lastname: Efros
authors.affiliation: Optical Sciences Division, Naval Research Laboratory , Code 5600, 4555 Overlook Avenue SW, Washington, DC 20375, United States.
authors.forename: Alan L
authors.initials: AL
authors.lastname: Huston
authors.affiliation: Center for Bio/Molecular Science and Engineering, Naval Research Laboratory , Code 6900, 4555 Overlook Avenue SW, Washington, DC 20375, United States.
authors.forename: James B
authors.initials: JB
authors.lastname: Delehanty
mesh_terms: D049449:Luminescence; D015335:Molecular Probes; D045663:Quantum Dots; D012666:Semiconductors
chemical_list: D015335:Molecular Probes
keywords: depolarization; electric field; fluorescence; lifetime; membrane potential; neuron; photoluminescence; quantum confined Stark effect; quantum dot; spike; voltage