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bioRxiv · 10.1101/2021.12.01.470798

iDEP-assisted isolation of insulin secretory vesicles

Barekatain, M.·Liu, Y.·Wang, Z.·Cherezov, V.·Fraser, S.·White, K. L.·Hayes, M. A.
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Abstract

Organelle heterogeneity and inter-organelle associations within a single cell contribute to the limited sensitivity of current organelle separation techniques, thus hindering organelle subpopulation characterization. Here we use direct current insulator-based dielectrophoresis (DC-iDEP) as an unbiased separation method and demonstrate its capability by identifying distinct distribution patterns of insulin vesicles from pancreatic {beta}-cells. A multiple voltage DC-iDEP strategy with increased range and sensitivity has been applied, and a differentiation factor (ratio of electrokinetic to dielectrophoretic mobility) has been used to characterize features of insulin vesicle distribution patterns. We observed a significant difference in the distribution pattern of insulin vesicles isolated from glucose-stimulated cells relative to unstimulated cells, in accordance with functional maturation of vesicles upon glucose stimulation, and interpret this to be indicative of high-resolution separation of vesicle subpopulation. DC-iDEP provides a path for future characterization of subtle biochemical differences of organelle subpopulations within any biological system.

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Barekatain, M., Liu, Y., Wang, Z., Cherezov, V., Fraser, S., White, K. L., Hayes, M. A.. 2021-12-01. iDEP-assisted isolation of insulin secretory vesicles. https://doi.org/10.1101/2021.12.01.470798

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