Human Pregnancy Specific Beta-1-Glycoprotein 2 ELISA Kit

This sandwich ELISA kit from Antibodies.com is designed for the in vitro quantitative determination of human Pregnancy Specific Beta-1-Glycoprotein 2 (PSG2) in serum, plasma, tissue homogenates, and other biological fluids. It is intended for use with a colorimetric microplate reader and is reactive with human samples.

The assay uses a pre-coated 96-well microplate onto which an antibody specific for PSG2 has been immobilised. Standards and test samples are added to the wells, where PSG2 is captured by the coated antibody. After washing, a biotinylated anti-PSG2 antibody is added and binds the captured PSG2. An HRP-avidin conjugate is then added, and following further incubation and washing the HRP enzymatic reaction is visualised with TMB substrate, producing a blue-coloured product that turns yellow upon addition of the acidic stop solution. The intensity of the yellow colour, read as absorbance at 450 nm, is proportional to the amount of PSG2 captured, and the concentration is calculated by reference to the standard curve. Total assay time is 4 hours 30 minutes.

Reported sensitivity is less than 0.066 ng/ml with an assay range of 0.156–10 ng/ml. Spike-and-recovery testing gave averages of 91% (range 80–102%) in serum (n=5), 90% (range 81–100%) in EDTA plasma (n=5) and 84% (range 80–89%) in heparin plasma (n=5). Linearity was demonstrated across 1:2, 1:4, 1:8 and 1:16 dilutions in serum (87–91%, 87–107%, 74–101%, 92–97%), EDTA plasma (90–105%, 84–101%, 90–101%, 79–108%) and heparin plasma (84–95%, 92–105%, 82–105%, 89–91%).