Rapid diagnosis of phenylketonuria and other aminoacidemias by quantitative analysis of amino acids in neonatal blood spots by gas chromatography-mass spectrometry.

A new method for quantifying specific amino acids in small volumes of plasma and whole blood has been developed. Volatile derivatives of amino acids are analyzed by gas chromatography-mass spectrometry. The method only takes a few minutes to perform and requires minimal sample preparation. The accurate assay of phenylalanine, tyrosine and other amino acids in dried blood spots could be used for neonatal screening for phenylketonuria and other aminoacidemias. Because of the low cost, this neonatal screening method is suited to application in developing countries such as China.