Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/7/2006
Publication Date: 3/24/2009
Citation: Byrdwell, W.C. 2009. Comparison of analysis of vitamin D3 in foods using ultraviolet and mass spectrometric detection. Journal of Agricultural and Food Chemistry. 57(6):2135-2146.
Interpretive Summary: There is increasing interest in vitamin D because inadequate intakes of vitamin D may play a role in contributing to many types of cancer, as well as heart disease, stroke, hypertension, autoimmune diseases and others. As the interest in vitamin D increases, there is a need for analytical methods that can be used to determine the amounts of vitamin D in common foods. This report shows a comparison of analytical methods for the determination of vitamin D by ultraviolet detection and by mass spectrometry. The results indicate that either method is suitable for most foods that contain vitamin D. However, some foods, such as processed cheese, contain substances that interfere with the analysis by UV detection, so mass spectrometry must be used to avoid erroneous results.
Technical Abstract: A method for analysis of vitamin D3 in commonly fortified foods and in fish, which contains endogenous vitamin D3, was developed by combining the best aspects of two official methods. The ethyl ether/petroleum ether extraction procedure from AOAC 992.26 was combined with the chromatographic separation and use of an internal standard (vitamin D2) from AOAC 2002.05 to produce a method that was applicable to a variety of food samples. Results for skim milk, orange juice, breakfast cereal, salmon, a diluted USP reference standard (vitamin D3 in peanut oil), and processed cheese are presented. Results indicated that UV detection was adequate in most cases, but the absence of interfering species must be determined in each food by mass spectrometry. Selected ion monitoring (SIM) atmospheric pressure chemical ionization (APCI) mass spectrometry (MS) was shown to produce statistically indistinguishable results between the two analytical methods for the skim milk, orange juice, multi-grain cereal and salmon samples. The processed cheese exhibited interferences that precluded quantification of vitamin D3 by UV detection, and so only SIM APCI-MS data for that sample were valid.