Fluorometric method for phenylalanine microplate assay adapted for phenylketonuria screening.

Abstract:

:We adapted the method of McCaman and Robins for fluorometry of phenylalanine to a microplate assay for routine phenylketonuria screening. Sensitivity is 15 mumol/L for the plasma assay and 30 mumol/L for the dried blood-spot assay, with CV less than 10% for both assays. Results for human plasma by microplate assay correlated well (r = 0.99) with results of amino acid analyzer determination of phenylalanine. When measurements are performed in an automated reader, the microplate assay has considerable advantages over conventional measurements in cuvettes: smaller volumes of reagents and automation enabling high throughput and convenience. Because the described method is a quantitative one, we can postulate that, compared with the semiquantitative Guthrie inhibition bioassay, this microplate assay is more reliable, easier to perform, and about twofold less costly.

journal_name

Clin Chem

journal_title

Clinical chemistry

authors

Gerasimova NS,Steklova IV,Tuuminen T

subject

Has Abstract

pub_date

1989-10-01 00:00:00

pages

2112-5

issue

10

eissn

0009-9147

issn

1530-8561

journal_volume

35

pub_type

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