Commercially-Supplied Binders for Plasma Cobalamin (Vitamin B12), Analysis-’ ‘Punt led” Intrinsic Factor, “Cobinamide’ ‘-Blocked R-Protein Binder, and Non-purified Intrinsic Factor-R-Protein Binder-Compared to Microbiological Assay
نویسندگان
چکیده
Recent evidence (Kolhouse et aL, N. EngI. J. Med. 299: 785-792, 1978) demonstrates that commercial cobalamin (Vitamin B12) radioassay kits contain nonspecific R-protein bindingagents thatcan give falsely normal results in patients who are actually cobalamin deficient. We tested three kits:with“purified” intrinsic factor as the binder, with intrinsic factor and the nonspecific R-protein sites blocked with “cobinamide,” and non-purified intrinsic factor-Rprotein binder. Results with use of the first two compared well with those by a microbiological assay (Lactobacillus Ieichmannh,) and are in harmony with clinical impressions.
منابع مشابه
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