SRM 2973 Vitamin D Metabolites in Frozen Human Serum (High Level) - This Standard Reference Material (SRM) is intended for use as an accuracy control in the critical evaluation of methods for determining the amount-of-substance concentration of vitamin D metabolites in human serum. This SRM can also be used as a quality assurance tool for assigning values to in-house control materials for these constituents. This data is public in the Certificate of Analysis for this material.

SRM 972a Vitamin D Metabolites in Frozen Human Serum - This Standard Reference Material (SRM) is intended for use as an accuracy control in the critical evaluation of methods for determining the amount-of-substance concentration of vitamin D metabolites in human serum. This SRM can also be used as a quality assurance tool for assigning values to in-house control materials for these constituents. This data is public in the Certificate of Analysis for this material.

Donor serum for SRM 2378 was collected from three groups of individuals: (level 1) three healthy donors who took 1000 mg/day of fish oil supplements for a minimum of one month prior to collection; (level 2) three healthy donors who took 1000 mg/day of flaxseed oil supplements for a minimum of one month prior to collection; and (level 3) three healthy donors who did not take either fish or flaxseed oil supplements for one month prior to collection. Value assignment of the mass fractions of the fatty acids in SRM 2378 was based on the results of one or two analytical methods at NIST and one analytical method at the Centers for Disease Control (CDC) with confirmation by data provided by an interlaboratory comparison. This data is public in the Certificate of Analysis for this material.

Donor serum for SRM 2378 was collected from three groups of individuals: (level 1) three healthy donors who took 1000 mg/day of fish oil supplements for a minimum of one month prior to collection; (level 2) three healthy donors who took 1000 mg/day of flaxseed oil supplements for a minimum of one month prior to collection; and (level 3) three healthy donors who did not take either fish or flaxseed oil supplements for one month prior to collection. Value assignment of the mass fractions of the fatty acids in SRM 2378 was based on the results of one or two analytical methods at NIST and one analytical method at the Centers for Disease Control (CDC) with confirmation by data provided by an interlaboratory comparison. This data is public in the Certificate of Analysis for this material.

,The database contains values for 506 food items for five subclasses of flavonoids:,

,This database was developed with support from the Office of Dietary Supplements, National Institutes of Health for flavonoid intake studies. The database is a useful tool for flavonoid intake and health outcome studies for any population globally. It contains data for 29 individual flavonoid compounds in six subclasses of flavonoids for every food in a subset of 2,926 food items which provide the basis for the Food and Nutrient Database for Dietary Studies (FNDDS 4.1). Proanthocyanidins data are not included at the present time. For flavonoid intake data for the U.S. population based on NHANES 2007-08, please refer to the Food Surveys Research Group website.,

SRM 1950 Metabolites in Frozen Human Plasma - This Standard Reference Material (SRM) is intended primarily for validation of methods for determining metabolites such as fatty acids, electrolytes, vitamins, hormones, and amino acids in human plasma and similar materials. This SRM can also be used for comparison of measurement technologies used in metabolomic studies and for quality assurance when assigning values to in-house reference materials. This SRM is intended to represent "normal" human plasma. A unit of SRM 1950 consists of five vials, each containing approximately 1.0 mL of plasma. This data is public in the Certificate of Analysis for this material.

SRM 3262 St. John's Wort (Hypericum perforatum L.) Aerial Parts - This Standard Reference Material (SRM) is intended primarily for use in validating analytical methods for the determination of chlorogenic acid, flavonoids, naphthodianthrones, and toxic elements in Hypericum perforatum L. and similar materials. This data is public in the Certificate of Analysis for this material.

SRM 3532 Calcium-Containing Solid Oral Dosage Form - This Standard Reference Material (SRM) is intended primarily for validation of methods for determining cholecalciferol (vitamin D3) and elements in a calcium dietary supplement and similar materials. This SRM can also be used for quality assurance when assigning values to in-house reference materials. A unit of SRM 3532 consists of five packets, each containing approximately 10 g of material. This data is public in the Certificate of Analysis for this material.