Description
For years, researchers have sought the ideal insulin assay that would combine absolute specificity with sensitivity, accuracy, low sample consumption, and ease-of-use. The search has come to an end! This serum insulin assay offers superior specificity and sensitivity for a reliable quantification of insulin in serum and plasma samples. Built on a truly homogeneous protocol, the assay does not require any washing or complex extraction steps, leading to significant time savings over ELISA methods.
HTRF assays offer many advantages over other technologies:
Homogeneous add-and-read format
No wash steps
Low background
Straightforward miniaturization from 96- or 384-well microplates to high density assay formats such as 384-well low volume and 1536-well plates
Stable signal, providing flexibility in time of readout or size of assays
Assay principle
Insulin is measured using a sandwich immunoassay of two monoclonal antibodies, one labelled with Cryptate (donor) and the other with XL665 (acceptor). The intensity of the FRET signal obtained is proportional to the concentration of insulin in the sample.
Assay protocol
10 µL of cell supernatants are supplemented with 10 µL of acceptor-labelled antibodies and 5 µL of donor-labelled antibodies (or 15 µL of pre-mixed reagents for a single dispensing step). The mix is then incubated from 4h to overnight at RT and results are read on an HTRF compatible reader.
Validation on normal mouse serum
C57BL/6J mice were randomized into two groups of 7 animals. One group was fasted overnight while the second one was normally fed. The mice were sacrificed and the blood was collected for serum preparation. The insulin concentration was determined in each sample using the HTRF Mouse Serum Insulin kit reagents.
Validation on diabetic mouse plasma
A group of five db/db diabetic male mice and a group of five db/+ control male mice were fasted overnight. The mice were sacrificed and the blood was collected through cardiac puncture for K3 EDTA-plasma preparation. The insulin concentration of each sample was determined using the HTRF Mouse Serum Insulin kit reagents.
Validation on obese mouse serum
A group of eight ob/ob obese mice and a group of eight ob/+ control mice were sacrificed and the blood was collected through cardiac puncture for serum preparation. The insulin concentration of each sample was determined using the HTRF Mouse Serum Insulin kit reagents.
