Start Date: Feb 22, 2009
End Date: Feb 21, 2014
Objective 1: Evidence-based reviews will provide priorities for specific vitamins, define adequacy of existing data, and define quality of data required for future needs. The present state of the performance of individual labs and the adequacy of analysis of specific vitamin measurement systems will be evaluated from extensive data available from the USDA contract analyses conducted as part of NFNAP and DSID. Clearly defined purpose statements will be developed for specific applications. Objective 2: Improved procedures will be developed to simultaneously measure water soluble vitamins (SIMWSV) [thiamin, riboflavin, niacin, pyridoxine, folic acid, pantothenic acid, biotin, choline, and ascorbic acid] in foods and dietary supplements (DS). SIMWSV and LC-IDMS methods for DS will be extended to fortified foods. The additional challenges of natural levels of vitamins in unfortified foods require different approaches or compromise conditions to obtain acceptable analytical results. We will examine newer chromatographic separation modes such as hydrophilic interaction liquid chromatography (HILIC) and aqueous normal phase (ANP) chromatography to improve these separations. A defined protocol of intra-laboratory validation will be carried out following AOAC guidelines. The FCMDLVitamin D method is implemented for analysis of food samples, and additional foods, dietary supplements and reference materials will be analyzed. IDMS methods will be initiated for other lipid soluble vitamins A, E, and K. The FCMDL method to determine the low levels of B12 in vitamin supplements using dual column LC/UV will be extended to fortified foods using sensitive LC/MS techniques and collaboratively cross-validated to the microbiological method. The possibility to calibrate spectral fingerprints (information with no chromatographic separation) of extracts of various types of food and dietary supplement materials to obtain quantitative information about vitamin content will be explored. Calibration models will be developed and validated. Objective 3: Multiple extractions for WSV with different buffers, pHs, and multiple extraction approaches (including classical and modern methods such as pressurized liquid extraction [PLE], microwave-assisted extraction [MAE], ultrasonic irradiation, stirring, shaking, and Soxhlet) will be systematically explored to ensure complete extraction and compare extraction efficiencies of different procedures. The lipid soluble vitamins (LSV) (A, D, E, K) would be similarily extracted with a organic solvents of different polarities. Objective 4: FCMDL capability for high quality vitamin determinations will be applied to provide reference measurements to value to NIST SRMs such as the Adult/Infant Formula SRM and Fortified Cereal SRM. Through initiating and providing guidance for a number of nutrition metrology-related activities, FCMDL will catalyze improvement of the overall measurement system for vitamins. FCMDL will participate as collaborators in method validation studies as appropriate. FCMDL will continue to organize and advise the development and conduct of symposia, and other appropriate workshops.