Human Secreted Frizzled Related Protein 4 ELISA Kit

A sandwich Enzyme-Linked Immunosorbent Assay (ELISA) from Antibodies.com, designed for the in vitro quantitative determination of human Secreted Frizzled Related Protein 4 (SFRP4) in serum, plasma or other biological fluids.

The assay uses the sandwich enzyme immunoassay technique. An antibody specific for SFRP4 is pre-coated onto a 96-well microtiter plate; standards and test samples are added, and captured SFRP4 is detected using a Biotinylated Anti-SFRP4 Antibody followed by an HRP-Avidin conjugate. The enzymatic reaction is visualised with TMB substrate, producing a yellow product whose intensity is read at 450 nm on a colorimetric microplate reader and quantified against a standard curve. Total assay time is 4 h 30 min, and kit components are stored at +4 °C or −20 °C as instructed.

Reported sensitivity is <26.6 pg/ml with a standard range of 62.5–4000 pg/ml. Average recovery values are 91% for serum (range 80–102%, n=5), 90% for EDTA plasma (range 81–100%, n=5) and 84% for heparin plasma (range 80–89%, n=5). Dilution linearity across 1:2, 1:4, 1:8 and 1:16 dilutions is reported as 87–91%, 87–107%, 74–101% and 92–97% 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.