Detection Method:Sandwich
Test principle:This assay employs a two-site sandwich ELISA to quantitate PG in samples. An antibody specific for PG has been pre-coated onto a microplate. Standards and samples are pipetted into the wells and anyPG present is bound by the immobilized antibody. After removing any unbound substances, a biotin-conjugated antibody specific for PG is added to the wells. After washing, Streptavidin conjugated Horseradish Peroxidase (HRP) is added to the wells. Following a wash to remove any unbound avidin-enzyme reagent, a substrate solution is added to the wells and color develops in proportion to the amount of PG bound in the initial step. The color development is stopped and the intensity of the color is measured.
Product Overview:Pepsin is an enzyme that whose precursor form (pepsinogen) is released by the chief cells in the stomach and that degrades food proteins into peptides. Pepsin was discovered in 1836 by Theodor Schwann who also coined this enzyme's name from the Greek word pepsis, meaning digestion (peptein: to digest). It was the first animal enzyme to be discovered, and, in 1929, it became one of the first enzymes to be crystallized, by John H. Northrop. Pepsin is a digestive protease.Pepsin functions best in acidic environments and is often found in an acidic environment, particularly those with a pH of 1.5 to 2. Pepsin denatures if the pH is more than 5.0.Pepsins should be stored at very cold temperatures (between ?20C and ?80C) to prevent autolysis (self-cleavage). Autolysis may also be prevented by storage of pepsins at pH 11 or by using modified pepsins (e.g., by reductive methylation). When the pH is adjusted back to 6.0 activity returns.
