Radioassay for cobalamin (vitamin B12) requiring no pretreatment of serum.

Abstract:

:We describe a radioassay for cobalamin (vitamin B12) in human serum or plasma that requires no boiling or other pretreatment of the sample. Normal chicken serum covalently coupled to magnetizable particles is used as the binding agent. The assay is performed at pH 12.9, at which pH all cobalamin in human serum is released from its binding proteins, whereas the binding agent maintains a high affinity for cobalamin (Ka 1.7 x 10(10) L/mol). Under these assay conditions the binding protein shows a specificity for cobalamin similar to that of purified intrinsic factor. The assay is simple, rapid, and precise, and results correlate well with those of the Euglena gracilis microbiological assay and an intrinsic-factor binding assay.

journal_name

Clin Chem

journal_title

Clinical chemistry

authors

Houts TM,Carney JA

subject

Has Abstract

pub_date

1981-02-01 00:00:00

pages

263-7

issue

2

eissn

0009-9147

issn

1530-8561

journal_volume

27

pub_type

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