Analysis of vitamin B12

Vitamin B12, also called cobalamin, is a water-soluble vitamin and one of the B complex vitamins that plays an important role in the functioning of the brain and nervous system as well as in the formation of red blood cells. Deficiency of vitamin B12 affects many biochemical parameters in the body. Therefore, many food, beverage and dietary supplements are fortified with vitamin B12 to help address any deficiencies in dietary requirements.

The predominant cobalamin forms are cyanocobalamin, hydroxylcobalamin, methylcobalamin and 5-deoxyadenosylcobalamin. Cyanocobalamin is the most widely used form of vitamin B12 in food and dietary supplements due to its availability and stability. In order to meet legal requirements, manufacturers label their products according to the country regulations where the product is consumed (for EU: European Commission 1925/2006 on the addition of vitamins and minerals).

Quantitative determination of vitamin B12 content is primarily performed to confirm label declarations.

The determination of cyanocobalamin has always been challenging because of the trace level input for vitamin B12 in these products (recommended daily intake for adults is only 2.4 μg and as for children it is even lower). Methods for the analysis of vitamin B12 include microbiological assay, spectrophotometric and various chromatographic techniques. Microbiological assays have been the most commonly used for the determination of vitamin B12 although these assays are time consuming, may lack specificity, and have high imprecision.

Therefore, high performance liquid chromatography is the most appropriate technique used for vitamin analysis in fortified foods and dietary supplements, however the determination of vitamin B12 at trace levels remains a challenge. Additional issue is the presence of other vitamins and interfering components in formulations. Currently, two-dimensional chromatography became one of the routine methods for detection of vitamin B12.

In our laboratory we have developed and validated a liquid chromatography method for quantification of vitamin B12 by using a single quadrupole mass analyser (ACQUITY QDa, Waters). Mass detection offers the opportunity to detect vitamins at lower levels that cannot be achieved with UV detection which is important for the quantification of the vitamins at trace levels (vitamins B7 in B12).

Improved sensitivity and selectivity helps us to deal with the wide variety of matrices and concentration ranges at which the vitamins are present in the formulations (starting from some μg to 1000 mg).

With QDa detector we are able to detect the vitamin B12 as well as other vitamins present in the formulation at much higher concentration levels. The mass detector is easily incorporated into existing workflows and offers more user friendly method compared to the multi-dimensional chromatographic methods. The results obtained from the routine analysis of various dietary supplements confirmed the suitability of the method for effective and robust quantification of vitamin B12.

METHOD FOR ANALYSIS OF VITAMIN B12

Our laboratory is specialized for method development, validation and employment of validated methods for accurate quantification of the active ingredients in various matrices. Furthermore, our contract laboratory can assist you with dietary supplements and nutraceuticals lab expertise, knowledge and support services such as: technical consulting, method development and validation, product comparison, competitor analysis etc. We would be pleased to carry out the analysis for you and provide quick, competent and reliable support.

Many more dietary supplement assays are available. If you require a specific assay contact us: info@inslab.si.