Evaluation of cyanocobalamin in multivitamin tablets and their Standard Reference Material 3280 by HPLC with visible detection.

As a part of the development of an alternative to microbiological assay for vitamin B12, we performed a quantitative analysis of cyanocobalamin (CN-cbl) in a National Institute of Standards and Technology Standard Reference Material (SRM 3280) by HPLC. Using this method, the observed value (4.64 microg/g) of CN-cbl in SRM 3280 was found to be in good agreement with the certified value (4.80 microg/g). The accuracy was over 95%, with a corresponding measurement precision value of 5%. To evaluate the applicability of the method on commercial multivitamin tablets, the method was applied to a variety of these samples. The present method has a good accuracy and precision to evaluate CN-cbl with respect to all of the examined tablets.