Human CASR/Extracellular calcium-sensing receptor ELISA Kit

This sandwich ELISA kit from Assay Genie is designed for the quantitative detection of human Extracellular Calcium-Sensing Receptor (CASR) in serum, plasma, cell culture supernatant, cell or tissue lysate, and other liquid samples. It uses a colorimetric double-antibody sandwich format with a reported sensitivity of 0.188 ng/mL and a working range of 0.313–20 ng/mL.

CASR is a G-protein-coupled receptor (Uniprot P41180) central to calcium homeostasis, with dysregulation linked to hypercalcemia, hypocalcemia, and disorders of bone metabolism. The kit is intended for metabolism research. Dilution linearity for serum was 86–105% at 1:2, 89–95% at 1:4, and 92–104% at 1:8 (n=5); EDTA plasma 88–100%, 83–100%, 86–96%; heparin plasma 87–99%, 81–99%, 83–94%. Spike-and-recovery averaged 94% for serum (range 88–103%), 95% for EDTA plasma (range 88–102%), and 94% for heparin plasma (range 85–102%).

The protocol involves equilibrating reagents to room temperature, a 90-minute primary incubation at 37 °C, 60 minutes with biotinylated detection antibody, 30 minutes with HRP-streptavidin, 10–20 minutes of TMB substrate development in the dark, and absorbance reading at 450 nm after adding stop solution. Kits should be stored at 2–8 °C for up to 12 months.