Principle of Assay
Human Sphingosine-1-phosphate ELISA Kit (A73746) is a 2 hour competitive Enzyme-Linked Immunosorbent Assay (cELISA) designed for the in vitro quantitative determination of human Sphingosine-1-phosphate in serum, plasma, tissue homogenates, and other biological fluids. A 96-well microtiter plate has been pre-coated with Sphingosine-1-phosphate. During the assay, Sphingosine-1-phosphate present in the standards or samples competes with immobilized Sphingosine-1-phosphate for binding to an assay-specific antibody. Following incubation, unbound components are removed by washing and HRP-Streptavidin conjugate is added to the wells. After further incubation and washing, TMB substrate solution is added to visualize the HRP enzymatic reaction. This produces a blue-coloured product that changes to yellow following addition of acidic stop solution. The intensity of the colour is measured at 450 nm using a microplate reader. The concentration of Sphingosine-1-phosphate in the samples is inversely proportional to the OD450 value and is determined by comparison with the standard curve.