Center for Bio/Molecular Science and Engineering, Naval Research Laboratory , Code 6900, 4555 Overlook Avenue SW, Washington, DC 20375, United States.
Optical Sciences Division, Naval Research Laboratory , Code 5600, 4555 Overlook Avenue SW, Washington, DC 20375, United States.
Nano Lett. 2015 Oct 14;15(10):6848-54. doi: 10.1021/acs.nanolett.5b02725. Epub 2015 Oct 2.
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.
量子点 (QDs) 的固有特性以及将其与活细胞进行可控界面结合的能力不断增强，在探测细胞膜动作电位等细胞过程方面具有广泛的潜在应用。我们证明，神经元膜中常见的电场会抑制量子点的光致发光 (PL)，并且首次表明，量子点的 PL 能够以毫秒级分辨率跟踪发射神经元的动作电位轮廓。事实证明，这种效应与电场驱动的量子点离子化以及随之而来的量子点 PL 猝灭有关，这与传统观点相反，传统观点认为量子点 PL 的抑制归因于量子限制斯塔克效应。
