ELISA法定量测定人血清、血浆、细胞培养物上清或其它相关液体中胃蛋白酶(Pepsin)含量。

本试剂盒应用双抗体夹心酶标免疫分析法测定标本中Pepsin水平。用纯化的抗体包被微孔板，制成固相抗体，往包被单抗的微孔中依次加入Pepsin抗原、生物素化的抗人Pepsin抗体、HRP标记的亲和素，经过彻底洗涤后用底物TMB显色。TMB在过氧化物酶的催化下转化成蓝色，并在酸的作用下转化成最终的黄色。颜色的深浅和样品中的Pepsin呈正相关。用酶标仪在450nm波长下测定吸光度（OD值），计算样品浓度。

This immunoassay kit allows for the specific measurement of human Pepsin concentrations in cell culture supernates, serum, and plasma.

Pepsin is an acidic protease. Its inactive zymogen precursor, pepsinogen, is produced in the stomach mucosa. There are several pepsins designated A, B, C, and D. Pepsin A, the major component, has a molecular weight of 35,000 daltons and an optimum pH of approximately 1.0 for substrates such as casein or hemoglobin if the substrate is native protein. Pepsin cleaves proteins preferentially at carboxylic groups of aromatic amino acids such as phenylalanine and tyrosine. It will not cleave at bonds containing valine, alanine or glycine. Pepsin is unstable above pH 6.

pepsin enzyme produced in the mucosal lining of the stomach that acts to degrade protein. Pepsin is one of three principal protein-degrading, or proteolytic, enzymes in the digestive system , the other two being chymotrypsin and trypsin . The three enzymes were among the first to be isolated in crystalline form. During the process of digestion, these enzymes, each of which is particularly effective in severing links between particular types of amino acids, collaborate to break down dietary proteins to their components, i.e., peptides and amino acids , which can be readily absorbed by the intestinal lining. In the laboratory studies pepsin is most efficient in cleaving bonds involving the aromatic amino acids, phenylalanine, tryptophan, and tyrosine. Pepsin is synthesized in an inactive form by the stomach lining; hydrochloric acid, also produced by the gastric mucosa, is necessary to convert the inactive enzyme and to maintain the optimum acidity ( p H 1-3) for pepsin function. Pepsin and other proteolytic enzymes are used in the laboratory analysis of various proteins; pepsin is also used in the preparation of cheese and other protein-containing foods.

This assay employs the quantitative sandwich enzyme immunoassay technique. A monoclonal

antibody specific for Pepsin has been pre-coated onto a microplate. Standards and samples are pipetted into the wells and any Pepsin present is bound by the immobilized antibody. An enzyme-linked polyclonal antibody specific for Pepsin is added to the wells. Following a wash to remove any unbound antibody-enzyme reagent, a substrate solution is added to the wells and color develops in proportion to the amount of Pepsin bound in the initial step. The color development is stopped and the intensity of the color is measured.