The Adsorption of Intrinsic Factor Concentrate to Glass: Occurrence and Prevention With Reference to Radioisotope Dilution Assays of Vitamin B₁₂

Adsorption of IFC-B₁₂ onto glass surfaces has been demonstrated at pH 4.0, 0.02 I, and has also been indicated under the conditions commonly occurring during the radioisotope dilution assay of vitamin B₁₂ levels by methods that use IFC. The addition of albumin prevents adsorption of IFC onto glass and it is suggested that this explains the reported necessity for adding albumin or other proteins to "IF control tubes" in such assays.