Phenylalanine determined in plasma with use of phenylalanine dehydrogenase and a centrifugal analyzer.
Quantitative determination of plasma phenylalanine (Phe) is essential for the diagnosis of phenylketonuria (PKU) and the control of dietary therapy of PKU patients. We have adapted a spectrophotometric method (Clin Chim Acta 1991;201:95-8) based on phenylalanine dehydrogenase (EC 1.4.1.-) for rapid and accurate determinations of Phe with the Cobas Fara II centrifugal analyzer. The method is based on the NAD(H)-dependent reductive deamination of Phe with large amounts of phenylalanine dehydrogenase, which catalyzes the formation of phenylpyruvate at pH 10.8. Combining the specificity of the phenylalanine dehydrogenase with the precision, accuracy, and considerable time-saving of an automated system is useful for monitoring PKU patients in a children's hospital.
Vilaseca
M A
MA
Servei de Bioquímica, Hospital Infantil Sant Joan de Déu, Barcelona, Spain.
Farré
C
C
Ramón
F
F
D000594:Amino Acid Oxidoreductases / Q000378:metabolism; D001322:Autoanalysis / Q000379:methods* / Q000592:standards / Q000706:statistics & numerical data; D006801:Humans; D009243:NAD / Q000378:metabolism; D010649:Phenylalanine / Q000097:blood*; D010661:Phenylketonurias / Q000097:blood*; D010667:Phenylpyruvic Acids / Q000378:metabolism; D011786:Quality Control
D010667:Phenylpyruvic Acids; D009243:NAD; D010649:Phenylalanine; D000594:Amino Acid Oxidoreductases; C022342:phenylalanine oxidase; C031606:phenylpyruvic acid