Human Interleukin 31 ELISA Kit

A sandwich Enzyme-Linked Immunosorbent Assay from Antibodies.com designed for the in vitro quantitative determination of human IL-31 in serum, plasma or other biological fluids. The assay uses a pre-coated 96-well microplate arranged as 12 x 8 well strips, with an antibody specific for IL-31 immobilised on the plate. Standards and test samples are added to the wells and IL-31 present in each sample is bound by the immobilised antibody. Following incubation and washing, a Biotinylated Anti-IL-31 Antibody is added, followed by an HRP-Avidin conjugate. TMB substrate solution is then used to visualise the HRP enzymatic reaction, producing a blue product that changes to yellow after addition of acidic stop solution. The density of yellow is proportional to the amount of IL-31 captured in each well, and the concentration is calculated from the absorbance read at 450 nm in a colorimetric microplate reader against the standard curve.

The kit has a reported sensitivity of <5.5 pg/ml and an assay range of 15.6-1000 pg/ml, with a total assay time of 4 hours 30 minutes. Spike-and-recovery testing gave averages of 91% in serum (n=5, range 83%-100%), 94% in EDTA plasma (n=5, range 91%-98%) and 94% in heparin plasma (n=5, range 90%-99%). Dilution linearity was demonstrated across 1:2, 1:4, 1:8 and 1:16 dilutions for serum, EDTA plasma and heparin plasma. Kit components are stored at +4°C or -20°C as instructed in the protocol manual, and the kit should not be used past its expiration date.