Islets of Langerhans are the endocrine portion of the pancreas responsible for maintaining glucose homeostasis via the regulated secretion of numerous hormones, most notably insulin and glucagon. Defects in the secretion of these hormones are associated with a number of metabolic diseases, including diabetes and the metabolic syndrome. The ability to measure these glucose-regulating peptides with high time resolution and sensitivity is necessary to fully resolve the secretion dynamics of these factors and to understand how they change at various disease stages.
In this talk, a number of analytical strategies our group has developed which enable monitoring of secretion with high time resolution will be discussed. These assays include multi-color electrophoretic affinity assays, electrochromatographic separations for small molecule transmitters, and fluorescence anisotropy immunoassays. A number of these assays have been integrated into microfluidic systems to enable monitoring of secretions as a function of time. Select applications of these devices will also be discussed including how groups of islets can coordinate their secretion in vivo into pulses that are necessary for proper glucose utilization.