Evaluating the potential of using quantum dots for monitoring electrical signals in neurons

Abstract

Success in the projects aimed at providing an advanced understanding of the brain is directly predicated on making critical advances in nanotechnology. This Perspective addresses the unique interface of neuroscience and nanomaterials by considering the foundational problem of sensing neuron membrane voltage and offers a potential solution that may be facilitated by a prototypical nanomaterial. Despite substantial improvements, the visualization of instantaneous voltage changes within individual neurons, whether in cell culture or in vivo, at both the single-cell and network level at high speed remains complex and problematic. The unique properties of semiconductor quantum dots (QDs) have made them powerful fluorophores for bioimaging. What is not widely appreciated, however, is that QD photoluminescence is exquisitely sensitive to proximal electric fields. This property should be suitable for sensing voltage changes that occur in the active neuronal membrane. Here, we examine the potential role of QDs in addressing the important challenge of real-time optical voltage imaging.

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Fig. 1: Schematic of signalling and membrane depolarization along the axon of a neuronal cell.
Fig. 2: QD photophysical properties.
Fig. 3: Effect of electric field on QD PL.
Fig. 4: In vitro and in vivo optical imaging of cortical electrical stimulation using QD−JBD1−C60 bioconjugates.

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Acknowledgements

A.L.E., J.B.D., A.L.H. and I.L.M. acknowledge the financial support of the Office of Naval Research (ONR) through the Naval Research Laboratory Basic Research Program and the NRL Nanoscience Institute. The work of M.B. and T.D.H. was supported by the Howard Hughes Medical Institute.

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Correspondence to Alexander L. Efros or Timothy D. Harris.

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Efros, A.L., Delehanty, J.B., Huston, A.L. et al. Evaluating the potential of using quantum dots for monitoring electrical signals in neurons. Nature Nanotech 13, 278–288 (2018). https://doi.org/10.1038/s41565-018-0107-1

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