Evaluation of pteroylglutamic acid and n-5-methyltetrahydrofolic acid reference standards in a new "No-Boil" radioassay for serum folate.

Abstract:

:Serum folate, pteroylglutamic acid standards, and N-5-methyltetrahydrofolate standards extract differently during sample preparation for radiometric assay. B/B0 values for each material were determined before and after an alkaline extraction procedure. Serum folate most closely resembled N-5-methyltetrahydrofolate standards in that it exhibited a slightly greater ability to displace iodinated folate derivative in competition for beta-lactoglobulin binder. Pteroylglutamic acid standards displaced folate derivative less well, so that serum folate values were lower than when N-5-methyltetrahydrofolate was used as the standard material.

journal_name

Clin Chem

journal_title

Clinical chemistry

authors

Theobald RA,Batchelder M,Sturgeon MF

subject

Has Abstract

pub_date

1981-04-01 00:00:00

pages

553-5

issue

4

eissn

0009-9147

issn

1530-8561

journal_volume

27

pub_type

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