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At least 73 records · Page 4Linked to original sources
PubMed2003

[Thrombin Reference Standard (Control 031) of National Institute of Health Sciences].

The "Thrombin Reference Standard (Control 031", of National Institute of Health Sciences was prepared. The precision of filling into ampoule was about 11.5% as C.V. The content of alpha-thrombin was about 89%. The thrombin potency of the standard material was assayed against the Thrombin Reference Standard (Control 961) according to the method of JP-X IV and the potency was 692 +/- 35 units/ampoule. From the results, the potency of the proposed material for Thrombin Reference Standard was defined as 690 units per ampoule.

Electrophoresis, Polyacrylamide Gel↗
PubMedDate not supplied

The certification of morphine and codeine in a human urine standard reference material.

The National Institute of Standards and Technology (NIST, formerly the National Bureau of Standards) has developed and certified a Standard Reference Material, SRM 2381, for use in testing for bias in determinations of morphine and codeine in human urine. Each unit of this SRM consists of three vials with different levels of morphine and codeine in lyophilized urine. Three different analytical methods, employing GC/MS, LC/MS, and MS/MS, were used to certify the concentrations of each analyte. Results from the three methods were in good agreement and, therefore, were statistically combined to yield certified values of 138, 293, and 578 ng/mL for morphine and 134, 283, and 591 for codeine. A round-robin study on this material among nine military laboratories demonstrated the suitability of the SRM for its intended purpose.

Chromatography, Liquid↗
PubMedDate not supplied

Preparation and characterization of a suite of ephedra-containing standard reference materials.

The National Institute of Standards and Technology, the U.S. Food and Drug Administration, Center for Drug Evaluation and Research and Center for Food Safety and Applied Nutrition, and the National Institutes of Health, Office of Dietary Supplements, are collaborating to produce a series of Standard Reference Materials (SRMs) for dietary supplements. A suite of ephedra materials is the first in the series, and this paper describes the acquisition, preparation, and value assignment of these materials: SRMs 3240 Ephedra sinica Stapf Aerial Parts, 3241 E. sinica Stapf Native Extract, 3242 E. sinica Stapf Commercial Extract, 3243 Ephedra-Containing Solid Oral Dosage Form, and 3244 Ephedra-Containing Protein Powder. Values are assigned for ephedrine alkaloids and toxic elements in all 5 materials. Values are assigned for other analytes (e.g., caffeine, nutrient elements, proximates, etc.) in some of the materials, as appropriate. Materials in this suite of SRMs are intended for use as primary control materials when values are assigned to in-house (secondary) control materials and for validation of analytical methods for the measurement of alkaloids, toxic elements, and, in the case of SRM 3244, nutrients in similar materials.

Alkaloids↗
PubMed1996

[Lysozyme Reference Standard (Control 951) of the National Institute of Health Sciences].

The "Lysozyme Reference Standard (Control 951)" of the National Institute of Health Sciences was prepared. The lysozyme potency of the standard material was assayed against the Lysozyme Reference Standard (Control 915) by two turbidimetric methods using the drycells of Micrococcus luteus as the substrate. The potency of the standard material was in satisfactory agreement with that of Lysozyme Reference Standard (Control 915) and was defined as 1 mg [potency] per mg.

Amino Acids↗
PubMed1998

[Kallidinogenase Reference Standard (Control 971) of National Institute of Health Sciences].

The "Kallidinogenase Reference Standard (Control 971)" of National Institute of Health Sciences was prepared. The kallidinogenase potency of the standard material was assayed against the 2nd Kallidinogenase Reference Standard (Control 854) by the enzyme assay method using H-D-valyl-L-leucyl-L-arginine-p-nitro-anilide as the substrate. The potency of the Kallidinogenase Reference Standard material thus obtained was defined as 119 unit per ampoule.

Government Agencies↗
PubMed2000

[Heparin Sodium Reference Standard (Control 991) of National Institute of Health Sciences].

The National Institute of Health Sciences Reference Standard for Heparin Sodium (Control 991) was prepared. The potency of heparin sodium for the candidate reference standard was assayed against "Heparin Sodium Reference Standard (Control 871)" by JP Method in collaboration with 4 laboratories, and estimated as 1,453 +/- 25 units per ampoule. The filling amounts of heparin sodium in ampoule was estimated as 7.46 +/- 0.15 mg per ampoule, and the precision of filling into ampoule was about 2.0% as C.V. Based on the above results, the candidate was defined as 1450 units per ampoule, and was authorized as the Heparin Sodium Reference Standard (Control 991) of the National Institute of Health Sciences.

Government Agencies↗
PubMed1996

Certification of fat-soluble vitamins, carotenoids, and cholesterol in human serum: Standard Reference Material 968b.

In Standard Reference Material 968b, fat-soluble vitamins and cholesterol in human serum, certified values are provided for cholesterol, retinol, retinyl palmitate, alpha-tocopherol, trans-beta-carotene, total beta-carotene ( trans plus cis isomers), total alpha-carotene, and lutein. Non-certified values are also reported for gamma-tocopherol (includes beta-tocopherol), delta-tocopherol, zeaxanthin, beta-cryptoxanthin, trans-lycopene, trans-lycopene, trans-alpha-carotene, total lycopene, 9- cis-betacarotene, 13- plus 15- cis-beta-carotene, and 15- cis-beta-carotene. Both certified and non-certified values are based on the agreement among results from three different liquid chromatographic analytical procedures developed at NIST and from an interlaboratory comparison exercise among institutions that participate in a NIST-managed Micronutrients Measurement Quality Assurance Program. Cholesterol is certified in this material using the NIST isotope dilution/mass spectrometric definitive method.

Journal Article↗
PubMed2004

Standard reference values for musculoskeletal ultrasonography.

OBJECTIVES: To determine standard reference values for musculoskeletal ultrasonography in healthy adults. METHODS: Ultrasonography was performed on 204 shoulders, elbows, hands, hips, knees, and feet of 102 healthy volunteers (mean age 38.4 years; range 20-60; 54 women) with a linear probe (10-5 MHz; Esaote Technos MP). Diameters of tendons, bursae, cartilage, erosions, hypoechoic rims around tendons and at joints were measured with regard to established standard scans. Mean, minimum, and maximum values, as well as two standard deviations (2 SD) were determined. Mean values +/-2 SD were defined as standard reference values. RESULTS: Hypoechoic rims were normally present in joints and tendon sheaths owing to physiological synovial fluid and/or cartilage. Similarly, fluid was found in the subdeltoid bursa in 173/204 (85%), at the long biceps tendon in 56 (27%), in the suprapatellar recess in 158 (77%), in the popliteal bursae in 32 (16%), and in the retrocalcaneal bursa in 49 (24%). Erosions of >1 mm were seen at the humeral head in 47 (23%). Values for important intervals were determined. The correlation between two investigators was 0.96 (0.78-0.99). The reliability of follow up investigations was 0.83 (0.52-0.99). CONCLUSIONS: Fluid in bursae as well as hypoechoic rims within joints and around tendons are common findings in healthy people. This study defines standard reference values for musculoskeletal ultrasonography to prevent misinterpretation of normal fluid as an anatomical abnormality.

Adult↗
PubMed1998

Fiber numbers per unit weight of JFM standard reference samples determined with a scanning electron microscope. Japan Fibrous Material.

A standard reference 10 sample-set of fibrous minerals were prepared by the Japan Fibrous Material Research Association (JFMRA) under the name of JMF standard reference samples. In this paper, the fiber number per unit weight of JFM standard reference samples was determined with a scanning electron microscope. Fiber numbers per unit weight (f/microgram) and standard deviations observed in this experiment were as follows: glass wool (GW1) 7.0 +/- 0.1 x 10(2), rock wool (RW1) 1.7 +/- 0.2 x 10(3), micro glass fiber (MG1) 6.5 +/- 0.4 x 10(4), refractory ceramic fibers; (RF1) 8.8 +/- 0.7 x 10(3), (RF2) 8.7 +/- 0.8 x 10(3), mullite fibers (RF3) 3.5 +/- 0.7 x 10(3), potassium titanate whisker (PT1) 5.9 +/- 0.3 x 10(5), silicon carbide whisker (SC1) 4.1 +/- 0.4 x 10(5), titanium oxide whisker (rutile) (TO1) 6.4 +/- 0.6 x 10(5), and wollastonite (WO1) 2.4 +/- 0.1 x 10(4). Fiber numbers per unit weight would change in proportion to the cube or cube root of the fiber size if the fibers have the same density and the same aspect ratio. JFM standard reference samples should be used taking into consideration the difference in fiber number per unit weight when users conduct in vitro and/or in vivo (injection) biological experiments using these samples.

Humans↗
PubMed2003

Value assignment of nutrient and aflatoxin concentrations in standard reference material 2387 peanut butter.

Standard Reference Material (SRM) 2387 peanut butter was recently issued, and the process used for value assignment of nutrient and aflatoxin concentrations is reported herein. Values were assigned using data provided by the National Institute of Standards and Technology (NIST) and collaborating laboratories. SRM 2387 is intended for use as a primary material for assigning values to in-house control materials and for validation of analytical methods for measurements in peanut butter and similar high-fat matrixes. SRM 2387 lies in sector 3 of AOAC International's fat-protein-carbohydrate triangle. With the addition of SRM 2387, NIST now offers materials within-or on the borders between-all sectors of the triangle. The Certificate of Analysis for SRM 2387 provides assigned values for concentrations of fatty acids, proximates, elements, and total dietary fiber, for which product labeling is required by the Nutrition Labeling and Education Act of 1990, as well as several vitamins, amino acids, and aflatoxins, for which labeling is not required. (Aflatoxin levels in peanut butter are regulated by the Food and Drug Administration.)

Aflatoxins↗
PubMed1997

Preparation and characteristics of standard reference samples of fibrous minerals for biological experiments.

Standard reference samples of fibrous minerals to be used for in vitro and in vivo (injection) biological experiments were prepared. Ten samples were selected from among the fibrous minerals currently used in industry: man-made mineral fibers (MMMF); glass wool (GW1), rock wool (RW1), micro glass fiber (MG1), refractory ceramic fibers (RF1, RF2), and mullite fibers (RF3), whiskers; potassium titanate (PT1), silicon carbide (SC1) and rutile (TlO2)(TO1), and a natural fibrous mineral; wollastonite (WO1). The MMMF samples were prepared by using the size-selective press method. The whisker samples and WO1 were all commercial products. The prepared samples were examined by X-ray diffraction and X-ray fluorescence analyses, and no impurities were identified in any of the samples at a level of 1%, although WO1 was found to have about 5% calcite and a trace amount of quartz (< 1%). The fiber sizes were measured by TEM. The geometric-mean length (micron), width (micron) and SD (in parenthesis) are: GW1 20.0 (2.58), 0.88 (3.10); RW1 16.5 (2.51), 1.80 (2.32); MG1 3.0 (2.22), 0.24 (2.35); RF1 12.0 (2.36), 0.77 (2.53); RF2 11.0 (1.96), 1.10 (2.00); RF3 11.0 (1.75), 2.40 (1.37); PT1 6.0 (2.04), 0.35 (1.51); SC1 6.40 (2.45), 0.30 (1.58); TO1 2.1 (2.00), 0.14 (1.53); WO1 10.5 (2.03), 1.00 (1.72). We concluded that these prepared fiber samples can be safely used for biological experiments. Sample sets containing about one gram of each sample known as JFM standard reference samples are provided by the Japan Fibrous Material Research Association (JFMRA).

Microscopy, Electron↗
PubMed1997

[Ulinastatin Reference Standard (Control 971) of the National Institute of Health Sciences].

The "Ulinastatin Reference Standard (control 971)" of National Institute of Health Sciences was prepared. The standard material was evaluated in collaboration with one domestic laboratory, and the potency of trypsin inhibiting activity was determined to be 3, 100 units/vial by relative assay method against the Ulinastatin Reference Standard (control 942). Other analytical data obtained were as follows: UV maximum absorption was observed at 277 nm, and the molecular weight was estimated to be about 66,300 by gel filtration method. Maximum variance of material contents in 10 vials was 2.29%. Based on the above results, this standard material was authorized to be the "Ulinastatin Reference Standard (control 971)" of the National Institute of Health Sciences.

Glycoproteins↗
PubMed2003

Quantification of the predominant monomeric catechins in baking chocolate standard reference material by LC/APCI-MS.

Catechins are polyphenolic plant compounds (flavonoids) that may offer significant health benefits to humans. These benefits stem largely from their anticarcinogenic, antioxidant, and antimutagenic properties. Recent epidemiological studies suggest that the consumption of flavonoid-containing foods is associated with reduced risk of cardiovascular disease. Chocolate is a natural cocoa bean-based product that reportedly contains high levels of monomeric, oligomeric, and polymeric catechins. We have applied solid-liquid extraction and liquid chromatography coupled with atmospheric pressure chemical ionization-mass spectrometry to the identification and determination of the predominant monomeric catechins, (+)-catechin and (-)-epicatechin, in a baking chocolate Standard Reference Material (NIST Standard Reference Material 2384). (+)-Catechin and (-)-epicatechin are detected and quantified in chocolate extracts on the basis of selected-ion monitoring of their protonated [M + H](+) molecular ions. Tryptophan methyl ester is used as an internal standard. The developed method has the capacity to accurately quantify as little as 0.1 microg/mL (0.01 mg of catechin/g of chocolate) of either catechin in chocolate extracts, and the method has additionally been used to certify (+)-catechin and (-)-epicatechin levels in the baking chocolate Standard Reference Material. This is the first reported use of liquid chromatography/mass spectrometry for the quantitative determination of monomeric catechins in chocolate and the only report certifying monomeric catechin levels in a food-based Standard Reference Material.

Atmospheric Pressure↗
PubMed2006

Characterization of the NIST seaweed Standard Reference Material.

The National Institute of Standards and Technology (NIST) Standard Reference Material (SRM) for seaweed was developed through an interlaboratory comparison with 24 participants from 16 countries. After evaluating different techniques to calculate certified values for the radionuclides, the median method was found to be the most representative technique. The certified values were provided for 13 radionuclides and information values were given for 15 more radionuclides. Results for the natural decay series showed disequilibrium in both the uranium and thorium series.

International Cooperation↗
PubMedDate not supplied

Recommendations for establishment of reference standards for recombinant-DNA-derived proteins and polypeptides.

An integrated approach is presented for the establishment of purified protein and peptide reference standard materials suitable for both biological and chemical assays. Preliminary considerations, handling and storage conditions, and a variety of chemical methods for defining the reference standards are examined in detail. Of the chemical methods, liquid chromatography (LC), amino acid analysis, Kjeldahl protein assay, electrophoresis, and ion chromatography are key assays in determining the potency, purity, and identity of the reference standard preparation. Finally, the role of liquid chromatography in assessing reference standards for identity and chemical purity is examined and correlated with other methods.

Amino Acids↗
PubMed2006

Dietary supplement Standard Reference Materials.

A new category of Standard Reference Materials (SRMs) based on dietary supplements is under development by the National Institute of Standards and Technology (NIST), with certified values for organic constituents and selected trace elements. These materials are provided primarily for use in method development and as control materials. The SRMs will assist manufacturers of dietary supplements in characterizing raw materials for potency, authenticity, and contamination or adulteration. In addition, the SRMs will assist in assessment of consistency and quality in finished products. The goal of this ongoing effort is to provide tools to the dietary supplement industry and measurement communities that will lead to improved quality of dietary supplements, and ultimately reduce public health risks that could potentially be associated with these products.

Dietary Supplements↗
PubMed1993

[Folic Acid Reference Standard (Control 921) of National Institute of Health Sciences].

Folic acid was tested for the preparation of "Folic Acid Reference Standard (Control 921)". The quality of the raw material was examined and compared with the previous Folic Acid Reference Standard (Control 862). Analytical data obtained were as follows: water content, 7.52%; free amines, 0.1%; infrared spectrum, the same as that of the JP Reference Standard; thin-layer chromatography, three impurities were detected; high-performance liquid chromatography (HPLC), two impurities were detected; assay, 101.2% by spectrophotometry at 550 nm and 100.4% by HPLC. Based on the above results, the raw material was authorized as the Japanese Pharmacopoeia Reference Standard (Control 921).

Chromatography, High Pressure Liquid↗