Micro-Albumin ELISA is a competitive test system for the quantitative measurement human albumin in urine.This product is intended for professional in vitro diagnostic use only.Highly purified human albumin is bound to microwells. The reaction is based on a competitive ELISA method with these steps:Calibrators, controls and urine samples are incubated together with anti-albumin-peroxidase conjugate in the wells. Albumin, if present, will compete with coated albumin for binding of the anti-albumin-conjugate. Washing of the microwells removes unspecific components. Bound enzyme conjugate will hydrolyze the enzyme substrate TMB. Theaddition of acid stops the reaction forming a yellow end-product. The intensity of this yellow colour is measured photometrically at 450 nm. The amount of colour is inversely proportional to the concentration of albumin present in the original sample.Proteins passing the glomerular basal membrane of the kidney undergo differentiated filtering. The permeability is inversely proportional to the molecular weight (albumin about 0.6 %, myoglobulin about 75 %). Nevertheless, only minimal quantities of protein are detectable in urine, because big quantities of protein are reabsorbed by the tubuli. Elevated glomerular protein permeability and high tubular plasma protein elimination can be differentiated by measuring the molecular weight distribution of the eliminated proteins.