Abstract:
:Phenylketonuria is an inherited metabolic disease, which is characterized by an increased level of serum phenylalanine. Quantitative measurement of phenylalanine in the serum of phenylketonuria patients is necessary to confirm the disease, and to distinguish phenylketonuria from other forms of hyperphenylalaninemia. In this study, we report a rapid and inexpensive micro-assay for simultaneous detection and quantitative measurement of serum phenylalanine on dry blood-spots. Analysis of the standard curve showed a broad linear range for phenylalanine from 120 to 1800 micromol/L. Application of this method, the standard Guthrie bacterial inhibition assay and a high-performance liquid chromatography (HPLC) method for analysis of 34 samples from phenylketonuria patients and control samples produced comparable results, with the regression equation Y = 0.994X + 0.996. The advantage of this method over the Guthrie bacterial inhibition assay is its ability to measure serum phenylalanine quantitatively without false positive results. The method was successfully applied to dried blood-spots, serum and whole blood. The cost per sample is approximately 20-50 US cents, which is much less than for HPLC and commercial enzyme kits. The method can be automated, and is thus suitable for neonatal and mass screening for phenylketonuria, especially in developing countries where funding is a limiting factor.
journal_name
Clin Chem Lab Medjournal_title
Clinical chemistry and laboratory medicineauthors
Vallian S,Moeini Hdoi
10.1515/CCLM.2006.015keywords:
subject
Has Abstractpub_date
2006-01-01 00:00:00pages
76-9issue
1eissn
1434-6621issn
1437-4331journal_volume
44pub_type
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