A quantitative ELISA-based assay for the detection of Human Retinol Binding Protein in biological samples. Each kit contains: an anti-Human Retinol Binding Protein sensitized 96-strip micro-well plate, 50 mL diluent, 50 mL concentrated wash solution, anti-Human Retinol Binding Protein conjugate, 12mL TMB substrate, 12mL stop solution and a retinol binding protein calibrator.