Biochemical Importance, Deficiency and Clinical Assay of Cyanocobalamin

ABSTRACT

The present review describes the biochemical importance of cyanocobalamin [vitamin B12] and its role in the biosynthesis of adenosylcobamide and methylcobamide co-enzymes which perform important functions in human metabolism. Cyanocobalamin deficiency is a significant public health problem particularly among the elderly. It has been reported that the prevalence of vitamin B12 deficiency may be as high as 30-40% among the elderly due to food B12 malabsorption. Various analytical methods have been used for the clinical assay of cyanocobalamin in biological samples. These include microbiological, radioisotope, spectrophotometric and chromatographic methods: