Polydimethylsiloxane (PDMS) prepolymer (Sylgard 184) -Dow Corning (Midland, MI)
Dextrose -Fisher Scientific (Pittsburgh, PA)
TR-FRET glucagon assay -Cisbio (Walthan, MA)
All other reagents were purchased from Sigma-Aldrich (St. Louis, MO) unless noted otherwise. All solutions were made with ultrapure DI water (NANOpure Diamond System, Barnstead International, Dubuque, IA). A balanced salt solution (BSS) was used for islet experiments which contained 125 mM NaCl, 5.9 mM KCl, 1.2 mM MgCl2, 2.4 mM CaCl2, 25 mM tricine, and brought to pH 7.4 before addition of 0.1% BSA.
Materials and Instrumentation
HTRF 96 well low volume plates
Spectramax iD5 plate reader
PDMS device was fabricated using previously described methods1