用纯化的抗体包被微孔板，制成固相载体，往包被抗LTF抗体的微孔中依次加入标本或标准品、生物素化的抗LTF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LTF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。
Intended use
This immunoassay kit allows for the for the in vitro quantitative determination of bovine Lactoferrin, LTF concentrations in cell culture supernates, serum, plasma and other biological fluids.
Introduction
Lactoferrin is an iron-binding glycoprotein that belongs to the transferrin family. It is present in breast milk, in epithelial secretions, and in the secondary granules of neutrophils. Lactoferrin is a pleiotropic factor with potent antimicrobial and immunomodulatory activities. Recently, we have shown that lactoferrin can also promote bone growth. At physiological concentrations, lactoferrin potently stimulates the proliferation and differentiation of primary osteoblasts and also acts as a survival factor inhibiting apoptosis induced by serum withdrawal. Lactoferrin also affects osteoclast formation and, in murine bone marrow culture, lactoferrin potently inhibits osteoclastogenesis. In vivo, local injection of lactoferrin above the hemicalvaria of adult mice results in substantial increases in the dynamic histomorphometric indices of bone formation and bone area.
Test principle
The microtiter plate provided in this kit has been pre-coated with an antibody specific to LTF. Standards or samples are then added to the appropriate microtiter plate wells with a biotin-conjugated polyclonal antibody preparation specific for LTF and Avidin conjugated to Horseradish Peroxidase (HRP) is added to each microplate well and incubated. Then a TMB substrate solution is added to each well. Only those wells that contain LTF, biotin-conjugated antibody and enzyme-conjugated Avidin will exhibit a change in color. The enzyme-substrate reaction is terminated by the addition of a sulphuric acid solution and the color change is measured spectrophotometrically at a wavelength of 450 nm ± 2 nm. The concentration of LTF in the samples is then determined by comparing the O.D. of the samples to the standard curve.
