Comparison of methods used in commercial kits for the assay of serum vitamin B₁₂

Abstract

Fourteen commercial kits for serum vitamin B12 assay have been assessed. The analytical performance and clinical correlation were used to rank the methods employed for the extraction of the vitamin from its binders and for the separation of 'bound' from 'unbound' counts. The introduction of extraction without boiling and the separation by attachment of the vitamin B12 binder to a solid matrix have not been shown to be generally better or worse than conventional methods.

Microbiological assay of blood serum for the vitamin B12status of dairy cows

“…However, the use of radioassays has been the subject of several reviews (e.g. LeFebvre et al 1980;Fish & Dawson, 1983), and it is clear that many are nonspecific or, in some cases, less specific than the microbiological assay which they are replacing.…”