High-resolution imaging of cellular dopamine efflux using a fluorescent nanosensor array

TitleHigh-resolution imaging of cellular dopamine efflux using a fluorescent nanosensor array
Publication TypeJournal Article
Year of Publication2017
AuthorsKruss, S, Salem, DP, Vuković, L, Lima, B, Ende, EV, Boyden, ES, Strano, MS
JournalProceedings of the National Academy of Sciences of the United States of America
Pagination1789 - 1794
Date Published2017
KeywordsCarbon nanotubes, Chemical signaling, Dopamine, Imaging, sensors

Intercellular communication via chemical signaling proceeds with both spatial and temporal components, but analytical tools, such as microfabricated electrodes, have been limited to just a few probes per cell. In this work, we use a nonphotobleaching fluorescent nanosensor array based on single-walled carbon nanotubes (SWCNTs) rendered selective to dopamine to study its release from PC12 neuroprogenitor cells at a resolution exceeding 20,000 sensors per cell. This allows the spatial and temporal dynamics of dopamine release, following K+ stimulation, to be measured at exceedingly high resolution. We observe localized, unlabeled release sites of dopamine spanning 100 ms to seconds that correlate with protrusions but not predominately the positive curvature associated with the tips of cellular protrusions as intuitively expected. The results illustrate how directionality of chemical signaling is shaped by membrane morphology, and highlight the advantages of nanosensor arrays that can provide high spatial and temporal resolution of chemical signaling. © 2017, National Academy of Sciences. All rights reserved.