Phenylalanine (PKU) Screening Assay
The Phenylalanine (PKU) neonatal Screening Assay Kit is an enzymatic Assay for measurement of LPhenylalanine in human newborn blood spots. For neonatal screening on Phenylketonuria.
The Phenylalanine of the blood spots is eluated using Trichloracetic acid (3 %) from the cellulose paper. After that the Phenylalanine is transformed by the enzyme Phenylalaninedehydrogenase to Phenylpyruvate. This reaction is coupled to the reduction of the coenzyme NAD+, present in the reaction mixture. The reduced NADH transforms in a redox reaction the added Tetrazolium salt to the yellow substrate Formazane. The amount of Formazane developed is proportional to the concentration of Phenylalanine in the sample. The color of the substrate can be measured with a photometer at 450 nm.