Nano Secondary Ion Mass Spectrometry Imaging of Dopamine Distribution Across Nanometer Vesicles
Artikel i vetenskaplig tidskrift, 2017

We report an approach to spatially resolve the content across nanometer neuroendocrine vesicles in nerve-like cells by correlating super high-resolution mass spectrometry imaging, NanoSIMS, with transmission electron microscopy (TEM). Furthermore, intracellular electrochemical cytometry at nanotip electrodes is used to count the number of molecules in individual vesicles to compare to imaged amounts in vesicles. Correlation between the NanoSIMS and TEM provides nanometer resolution of the inner structure of these organelles. Moreover, correlation with electrochemical methods provides a means to quantify and relate vesicle neurotransmitter content and release, which is used to explain the slow transfer of dopamine between vesicular compartments. These nanoanalytical tools reveal that dopamine loading/unloading between vesicular compartments, dense core and halo solution, is a kinetically limited process. The combination of NanoSIMS and TEM has been used to show the distribution profile of newly synthesized dopamine across individual vesicles. Our findings suggest that the vesicle inner morphology might regulate the neurotransmitter release event during open and closed exocytosis from dense core vesicles with hours of equilibrium needed to move significant amounts of catecholamine from the protein dense core despite its nanometer size.

electrochemistry

NanoSIMS

nanoimaging

vesicle content

nanocompartments

Författare

Jelena Lovric

Chalmers, Kemi och kemiteknik, Kemi och biokemi, Analytisk kemi

Johan Dunevall

Chalmers, Kemi och kemiteknik, Kemi och biokemi, Analytisk kemi

Anna Larsson

Göteborgs universitet

Lin Ren

Chalmers, Kemi och kemiteknik, Kemi och biokemi, Analytisk kemi

Shalini Andersson

AstraZeneca AB

Anders Meibom

Ecole Polytechnique Federale De Lausanne

Per Malmberg

Chalmers, Kemi och kemiteknik, Kemi och biokemi, Analytisk kemi

Michael Kurczy

AstraZeneca AB

Andrew Ewing

Chalmers, Kemi och kemiteknik, Kemi och biokemi, Analytisk kemi

ACS Nano

1936-0851 (ISSN) 1936-086X (eISSN)

Vol. 11 4 3446-3455

Ämneskategorier

Kemi

DOI

10.1021/acsnano.6b07233