Bovine Interleukin 4 ELISA Kit

Manufactured by Antibodies.com, this Bovine Interleukin 4 (IL-4) ELISA Kit is a quantitative sandwich enzyme-linked immunosorbent assay designed for the in vitro determination of bovine IL-4 in serum, plasma, tissue homogenates, cell lysates, cell culture supernates and other biological fluids. The assay is reactive with bovine samples and uses a pre-coated microplate platform arranged as 12 x 8 well strips, with a total assay time of approximately 4 hours 30 minutes.

The kit employs the sandwich ELISA principle. An antibody specific for IL-4 is pre-coated onto the 96-well microtiter plate. Standards and test samples are added, and IL-4 present in each sample is bound by the immobilized antibody. Following incubation and washing, a Biotinylated Anti-IL-4 Antibody is added to bind the captured IL-4. After further washing, HRP-Avidin conjugate is added and incubated. TMB substrate is then used to visualize the HRP enzymatic reaction, producing a blue-coloured product that changes to yellow upon addition of the acidic stop solution. The intensity of yellow colour is proportional to the amount of IL-4 captured in each well, and the concentration is calculated by reading absorbance at 450 nm in a microplate reader and comparing to the standard curve.

The assay has a measuring range of 15.6-1000 pg/ml and a sensitivity of <5.9 pg/ml. In spiked recovery validation (n=5), average recoveries were 91% in serum (range 80-102%), 90% in EDTA plasma (range 81-99%) and 84% in heparin plasma (range 80-89%). Linearity across dilutions of 1:2, 1:4, 1:8 and 1:16 yielded recoveries of 87-91%, 87-107%, 74-101% and 92-97% respectively for serum; 90-105%, 84-101%, 90-101% and 79-108% for EDTA plasma; and 84-95%, 92-105%, 82-105% and 89-91% for heparin plasma. Kit components should be stored at +4°C or -20°C as instructed and the kit should not be used past its expiration date.