Human Programmed Cell Death Protein 1 Ligand 1 ELISA Kit

Manufactured by Antibodies.com, this sandwich ELISA is intended for the in vitro quantitative determination of human Programmed Cell Death Protein 1 Ligand 1 (PD-L1) in tissue homogenates, cell lysates, cell culture supernates, or other biological fluids. The procedure uses a pre-coated 96-well microplate (12 x 8 well strips) bearing an immobilised antibody specific for PD-L1, followed by incubation with a biotinylated anti-PD-L1 antibody and an HRP-avidin conjugate. The reaction is visualised with TMB substrate, producing a blue product that changes to yellow after the addition of acidic stop solution; the absorbance is read at 450 nm on a colorimetric microplate reader and PD-L1 concentration is calculated by reference to a standard curve.

The assay has a stated run time of 4h 30m, a product range of 0.156–10 ng/ml and a sensitivity of <0.066 ng/ml. Reported recovery values for spiked samples (n=5) are: serum 80%–102% (average 91%), EDTA plasma 81%–101% (average 91%), and heparin plasma 80%–89% (average 84%). Dilution linearity values across 1:2, 1:4, 1:8 and 1:16 sample dilutions are also provided for serum, EDTA plasma and heparin plasma.

Supplied components comprise the pre-coated 96-well microplate, two vials of lyophilised standard, 120 μl of detection solution A, 120 μl of detection solution B, 20 ml of 30X wash buffer, 45 ml of sample dilution buffer, 9 ml of TMB substrate, 6 ml of stop solution, and five adhesive plate sealers, with individual component storage temperatures ranging from +4°C to -20°C as detailed in the product insert. The instructions state that the kit should not be used past its expiration date.