Ultrasmall Analytical Chemistry: Biogenic Amines in the Fly Brain and in Single Transmitter Vesicles

New microanalytical approaches are being developed to study neurochemistry in extremely small environments: 1) the fruit fly, Drosophila melanogaster, and 2) single transmitter vesicles. We are developing and applying small sample handling and capillary electrophoresis methods for studies on the fly. These methods have produced some of the richest electropherograms or chromatograms for electrochemical detection of a biological sample reported to date and there are many compounds eluted that we have not yet identified. In addition, we are developing new protocols for in vivo voltammetry in the 8-nL brain of the fly. This presents the smallest in vivo approach in an intact organism and is an exciting analytical challenge. We are developing capillary electrophoretic separations of individual nanometer vesicles coupled to microfluidics for lysing and detection to develop a novel method to analyze neurotransmitter vesicles. Initial experiments with pheochromocytoma (PC12) cells have shown that only a fraction of the transmitter in a vesicle is released in normal exocytosis. We are working to expand this technology to several systems. The impact of the Drosophila work is in the use of these newly developed methods to understand the chemical mechanisms that underlie neurotransmission and drug addiction. The impact of the single vesicle work will be in the development of attoliter analysis strategies and to better understand the exocytosis process.

Swedish Research Council (VR)

Published: Mon 28 Oct 2013.