Lactoferrin ELISA

Lactoferrin is a multifunctional iron-binding protein with antimicrobial acitivities. It is found in milk and other mucosal secretions. Lactoferrin is known to be part of the innate defense against infection and inflammation and also has function in regulation of iron absorption.

In this assay the lactoferrin (LF) present in samples reacts with the anti-lactoferrin antibodies which have been adsorbed to the surface of polystyrene microtiter wells. After the removal of unbound proteins by washing, antilactoferrin antibodies conjugated with horseradish peroxidase (HRP), are added. These enzyme-labeled antibodies form complexes with the previously bound lactoferrin. Following another washing step, bound enzyme-conjugated antibody is assayed by the addition of a chromogenic substrate, 3,3’,5,5’- tetramethylbenzidine (TMB). The quantity of enzyme present varies directly with the concentration of LF in the sample tested; thus, the absorbance, at 450 nm, is a measure of the concentration of lactoferrin in the test sample. The quantity of lactoferrin in the test sample can be interpolated from the standard curve constructed from the standards and corrected for sample dilution.