Human Health

The accuracy of clinical diagnostic measurements is essential for reliable diagnosis and cost-effective treatment of disease. NIST's involvement includes reference methods, reference materials, and quality assurance programs to support the accuracy of health-related measurements. 

NIST works closely with the community to identify and address reference material and methods needs, and to ensure that these Standard Reference Materials (SRMs) are commutable with routine clinical assays. NIST is continually expanding the range of SRMs available, including primary standards, calibration materials, and matrix matched validation materials. These reference methods and the associated SRMs provide critical traceability and help improve the reliability of routine clinical measurements. 

Project Areas

Classical Clinical Metabolites/Markers

Assessment of health and disease status often requires the determination of clinical biomarkers and metabolites, measured in biofluids such as blood, serum, or urine. Accurate measurement of these analyte levels is critical.

NIST develops serum-based Standard Reference Materials (SRMs) that can be used as control materials by laboratories measuring clinical markers in human biofluids.

Nutritional Status Markers

A variety of nutrients are essential for normal functioning of the human body, and deficiencies can lead to serious illnesses. Accurate measurement of vitamin and vitamin metabolite levels is therefore critical for identifying individuals affected by nutritional deficiencies and for evaluating the potential health benefits associated with dietary supplementation. Assessment of nutritional status has been performed by a variety of techniques, including microbiological, enzymatic, immunoassay, and chromatographic approaches. Interlaboratory comparisons have revealed discrepancies in the results obtained by laboratories using different assay methods or even when different laboratories use the same assay for a given analyte. Such variation adds significant complexity to the identification of "normal" ranges for nutritional analytes, and reduces the reliability of vitamin deficiency diagnoses. To improve the accuracy and reliability of nutritional status assessments, NIST develops serum-based Standard Reference Materials (SRMs) that can be used as control materials by laboratories measuring nutritional status markers in human serum.

Reference Materials for Non-targeted Metabolomics, Lipidomics and Proteomics

The use of metabolite, lipid, and protein profiles for systems biology, biomedical research, and clinical applications has risen dramatically over recent years. Global profiling allows for the detection, identification and relative quantification of candidate biomarkers, or more specifically molecular markers, which discriminate disease processes, oxidative stress, injury, histopathological changes, pathophysiological mechanisms, drug effects, glycosylation, etc.  This technique has matured so that it is now possible to observe 1000s – 10,000s of unknown chemical compounds and different protein groups from cell lysates, bio-fluids and tissue samples, with the ability to gather simultaneous data of features much like RNA sequencing.  This non-targeted data analysis approach can highlight gross differences between sample groups and can be further queried by targeted quantitative analysis for specific proteins and/or biomarkers of interest.  However, due to the nature of detection, it is difficult if not impossible to relate data between instrument runs or amongst similar studies without a common internal standard or QC check.

Primary Standards for Clinical Metrology

NIST develops calibrants for organic chemical measurement that provide SI traceability through direct means and suitable for widely applicable clinical measurement procedures.

Quality Assurance Programs

NIST has extensive experience in the administration of interlaboratory comparisons and quality assurance programs (QAPs). These programs support the clinical measurement community by allowing participants to identify measurement challenges, improve the accuracy of their measurements, and demonstrate an effort to comply with various regulations. There is also the opportunity for laboratories to assess their in-house measurements, and, in conjunction with the use of SRMs, improve the comparability and precision of data over time.

The NIST Clinical Quality Assurance Program (ClinQAP) served two key functions in the clinical measurement community. The first was to support the long-term reliability of micronutrient, vitamin D metabolite, and fatty acid measurements in serum and plasma matrices through the Micronutrients Measurement Quality Assurance Program (MMQAP), the Vitamin D Metabolites Quality Assurance Program (VitDQAP), and the Fatty Acids in Human Serum and Plasma Quality Assurance Program (FAQAP), respectively. Results from the comparison studies helped participants to make accurate clinical and health-care decisions as well as to maintain and improve their measurement comparability. The second function of the ClinQAP was to monitor and support the emerging measurement needs of the clinical community and to expand the range of analytes and matrices studied.  The ClinQAP concluded in 2017, and parts of the ClinQAP community will now be served through the Health Assessment Measurements Quality Assurance Program (HAMQAP).

While quality assurance programs are conducted similarly to proficiency testing (PT), NIST programs are not PT and are not designed to pass strict evaluation of laboratory performance.  While proof of participation in NIST QAPs may be adequate to demonstrate proficiency in some communities, the use and distribution of each participant’s study results for this purpose will be at the discretion of the participant only.

 

CUSTOMERS/CONTRIBUTORS/COLLABORATORS

• American Association for Clinical Chemistry
• College of American Pathologists
• Centers for Disease Control and Prevention
• International Federation of Clinical Chemistry
• Mayo Clinic
• National Kidney Disease Education Program
• National Institutes of Health National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
• New York State Department of Public Health
• Office of Dietary Supplements (ODS) at the National Institutes of Health

 

SELECTED REFERENCES 

1. Camara, J. E., Pritchett, J. S., Daniels, Y. C., Bedner, M., Nelson, M. A., Lowenthal, M. S., Fazili, Z., Pfeiffer, C. M., Phinney, K. W., Sharpless, K. E., Sander, L. C., Lippa, K. A., Yen, J. H., Kuszak, A. J., and Wise, S. A., "Development of an improved standard reference material for folate vitamers in human serum," Analytical and Bioanalytical Chemistry, 415, 809-821 (2023). 

2. Kilpatrick, L. E., Bouillon, R., Davis, W. C., Henderson, C. M., Hoofnagle, A. N., Pauwels, S., Vanderschueren, D., Waelkens, E., Wildiers, H., Yen, J. H., and Phinney, K. W., "The influence of proteoforms: assessing the accuracy of total vitamin D-binding protein quantification by proteolysis and LC-MS/MS," Clinical Chemistry and Laboratory Medicine, 61, 78-85 (2023). 

3. Sempos, C. T., Williams, E. L., Carter, G. D., Jones, J., Camara, J. E., Burdette, C. Q., Hahm, G., Nalin, F., Duewer, D. L., Kuszak, A. J., Merkel, J., Hoofnagle, A. N., Lukas, P., Cavalier, E., Durazo-Arvizu, R. A., Crump, P. M., Popp, C., Beckert, C., Schultess, J., Van Slooten, G., Tourneur, C., Pease, C., Kaul, R., Villarreal, A., Ivison, F., Fischer, R., van den Ouweland, J. M. W., Ho, C. S., Law, E. W. K., Simard, J. N., Gonthier, R., Holmquist, B., Batista, M. C., Meadows, S., Cox, L., Jansen, E., Khan, D. A., Robyak, K., Creer, M. H., Kilbane, M., Twomey, P. J., Freeman, J., Parker, N., Yuan, J. Y., Fitzgerald, R., Mushtaq, S., Clarke, M. W., Breen, N., Simpson, C., and Wise, S. A., "Assessment of serum total 25-hydroxyvitamin D assays for Vitamin D External Quality Assessment Scheme (DEQAS) materials distributed at ambient and frozen conditions," Analytical and Bioanalytical Chemistry, 414, 1015-1028 (2022). 

4. Wise, S. A., Camara, J. E., Burdette, C. Q., Hahm, G., Nalin, F., Kuszak, A. J., Merkel, J., Durazo-Arvizu, R. A., Williams, E. L., Popp, C., Beckert, C., Schultess, J., Van Slooten, G., Tourneur, C., Pease, C., Kaul, R., Villarreal, A., Batista, M. C., Pham, H., Bennett, A., Jansen, E., Khan, D. A., Kilbane, M., Twomey, P. J., Freeman, J., Parker, N., Mushtaq, S., Simpson, C., Lukas, P., Cavalier, E., and Sempos, C. T., "Interlaboratory comparison of 25-hydroxyvitamin D assays: Vitamin D Standardization Program (VDSP) Intercomparison Study 2-Part 2 ligand binding assays - impact of 25-hydroxyvitamin D-2 and 24R,25-dihydroxyvitamin D-3 on assay performance,"  Analytical and Bioanalytical Chemistry, 414, 351-366 (2022). 

5. Wise, S. A., Camara, J. E., Burdette, C. Q., Hahm, G., Nalin, F., Kuszak, A. J., Merkel, J., Durazo-Arvizu, R. A., Williams, E. L., Hoofnagle, A. N., Ivison, F., Fischer, R., van den Ouweland, J. M. W., Ho, C. S., Law, E. W. K., Simard, J. N., Gonthier, R., Holmquist, B., Meadows, S., Cox, L., Robyak, K., Creer, M. H., Fitzgerald, R., Clarke, M. W., Breen, N., Lukas, P., Cavalier, E., and Sempos, C. T., "Interlaboratory comparison of 25-hydroxyvitamin D assays: Vitamin D Standardization Program (VDSP) Intercomparison Study 2-Part 1 liquid chromatography - tandem mass spectrometry (LC-MS/MS) assays - impact of 3-epi-25-hydroxyvitamin D-3 on assay performance," Analytical and Bioanalytical Chemistry, 414, 333-349 (2022). 

6. Yandrofski, K., Mouchahoir, T., De Leoz, M. L., Duewer, D., Hudgens, J. W., Anderson, K. W., Arbogast, L., Delaglio, F., Brinson, R. G., Marino, J. P., Phinney, K., Tarlov, M., and Schiel, J. E., "Interlaboratory Studies Using the NISTmAb to Advance Biopharmaceutical Structural Analytics," Frontiers in Molecular Biosciences, 9, (2022). 

7. Panteghini, M., Braga, F., Camara, J. E., Delatour, V., Van Uytfanghe, K., Vesper, H. W., and Zhang, T. J., "Optimizing Available Tools for Achieving Result Standardization: Value Added by Joint Committee on Traceability in Laboratory Medicine (JCTLM)," Clinical Chemistry, 67, 1590-1605 (2021). 

8. Sterrett, M. E., Bloom, M. S., Jamro, E. L., Wenzel, A. G., Wineland, R. J., Unal, E. R., Brock, J., Kucklick, J., Garcia, K., and Newman, R. B., "Maternal Food and Beverage Consumption Behaviors and Discrepant Phthalate Exposure by Race," International Journal of Environmental Research and Public Health, 18, (2021). 

9. Wenzel, A. G., Reiner, J. L., Kohno, S., Wolf, B. J., Brock, J. W., Cruze, L., Newman, R. B., and Kucklick, J. R., "Biomonitoring of emerging DINCH metabolites in pregnant women in charleston, SC: 2011-2014," Chemosphere, 262, (2021). 

10. Bearden, D. W., Sheen, D. A., Simon-Manso, Y., Benner, B. A., Rocha, W. F. C., Blonder, N., Lippa, K. A., Beger, R. D., Schnackenberg, L. K., Sun, J. C., Mehta, K. Y., Cheema, A. K., Gu, H. W., Marupaka, R., Gowda, G. A. N., and Raftery, D., "Metabolomics Test Materials for Quality Control: A Study of a Urine Materials Suite," Metabolites, 9, (2019). 

11. Bloom, M. S., Wenzel, A. G., Brock, J. W., Kucklick, J. R., Wineland, R. J., Cruze, L., Unal, E. R., Yucel, R. M., Jiyessova, A., and Newman, R. B., "Racial disparity in maternal phthalates exposure; Association with racial disparity in fetal growth and birth outcomes," Environment International, 127, 473-486 (2019). 

12. Casu, F., Watson, A. M., Yost, J., Leffler, J. W., Gaylord, T. G., Barrows, F. T., Sandifer, P. A., Denson, M. R., and Bearden, D. W., "Investigation of graded-level soybean meal diets in red drum (Sciaenops ocellatus) using NMR-based metabolomics analysis," Comparative Biochemistry and Physiology D-Genomics & Proteomics, 29, 173-184 (2019). 

13. Davis, W. C., Kilpatrick, L. E., Ellisor, D. L., and Neely, B. A., "Characterization of a human liver reference material fit for proteomics applications," Scientific Data, 6, (2019). 

14. Liu, Q. D., Liu, H., Chen, Y. Z., Yong, S. R., Teo, H. L., Wong, L. K., Teo, T. L., Vamathevan, V., do Rego, E. C. P., Wollinger, W., Fernandes, J. L. N., Monteiro, T. M., Garrido, B. C., Violante, F. M., Shi, L. H., He, H. H., Quan, C., Xu, B., Li, H. M., Dai, X. H., He, Y. J., Lo, M. F., Yip, Y. C., Cabillic, J., Delatour, V., Ohlendorf, R., Henrion, A., Kawaguchi, M., Kang, D., Lee, H., Osuna, M. A., Serrano, V., Arzate, C. M. S., Krylov, A., Lopushanskaya, E., Nammoonnoy, J., Goren, A. C., Gunduz, S., Yilmaz, H., Mussell, C., Warren, J., Pritchett, J. S., Lippa, K., Nelson, M. A., Toman, B., Sniegoski, L. T., and Duewer, D., "High polarity analytes in biological matrix: determination of urea and uric acid in human serum (CCQM-K109)," Metrologia, 56, (2019). 

15. Teo, T. L., Lippa, K. A., Mackay, L., Yong, S., Liu, Q. D., Camara, J. E., Delatour, V., Lee, T. K., Lalere, B., O'Connor, G., Henrion, A., Kato, M., Numata, M., Kwon, H. J., Jeong, J. S., Xu, B., Song, D. W., Nammoonnoy, J., and Wollinger, W., "Enhancing the accuracy of measurement of small molecule organic biomarkers," Analytical and Bioanalytical Chemistry, 411, 7341-7355 (2019). 

16. Teo, T. L., Liu, Q. D., Cheow, P. S., Duewer, D., Lippa, K., Toman, B., Osuna, M. A., Serrano, V., Arzate, C. M. S., Wong, L. K., Chen, Y. Z., Yong, S., Teo, H. L., Liu, H., Tong, B., Kang, D., Lee, H., Dai, X. H., Quan, C., Shi, L. H., Li, H. M., and Pritchett, J. S., "Comparison of CRMs and value-assigned quality controls: urea and uric Acid in human serum or plasma (CCQM-K142)," Metrologia, 56, (2019). 

17. Benner, B. A., Schantz, M. M., Powers, C. D., Schleicher, R. L., Camara, J. E., Sharpless, K. E., Yen, J. H., and Sniegoski, L. T., "Standard Reference Material (SRM) 2378 fatty acids in frozen human serum. Certification of a clinical SRM based on endogenous supplementation of polyunsaturated fatty acids," Analytical and Bioanalytical Chemistry, 410, 2321-2329 (2018). 

18. Miller, W. G., Schimmel, H., Rej, R., Greenberg, N., Ceriotti, F., Burns, C., Budd, J. R., Weykamp, C., Delatour, V., Nilsson, G., MacKenzie, F., Panteghini, M., Keller, T., Camara, J. E., Zegers, I., and Vesper, H. W., "IFCC Working Group Recommendations for Assessing Commutability Part 1: General Experimental Design," Clinical Chemistry, 64, 447-454 (2018). 

19. Sheen, D., Benner, B., Simon, Y., Rocha, W. F. C., Jones, C., Blonder, N., and Lippa, K., "Data harmonization in metabolomics for quality assurance and control," Abstracts of Papers of the American Chemical Society, 256, (2018). 

20. Shin, R., Dewi, F., Tong, B., Wah, L. H., Saxby, D., Armishaw, P., Ivanova, V., Feng, L. X., Wang, J., Busto, M. E. D., Fisicaro, P., Rienitz, O., Fung, W. H., Yau, M. H. P., Yim, Y. H., Buzoianu, M., Can, S. Z., Ari, B., Cankur, O., Infante, H. G., Perez-Zambra, R., Ferreira, E., Long, S., Davis, W. C., and Easley, R. A., "CCQM-K139 Elements in Human Serum," Metrologia, 55, (2018). 

21. Wang, L. Q., Bernert, J. T., Benowitz, N. L., Feng, J., Jacob, P., McGahee, E., Caudill, S. P., Scherer, G., Scherer, M., Pluym, N., Doig, M. V., Newland, K., Murphy, S. E., Caron, N. J., Sander, L. C., Shimizu, M., Yamazaki, H., Kim, S., Langman, L. J., Pritchett, J. S., Sniegoski, L. T., Li, Y., Blount, B. C., and Pirkle, J. L., "Collaborative Method Performance Study of the Measurement of Nicotine, Its Metabolites, and Total Nicotine Equivalents in Human Urine," Cancer Epidemiology Biomarkers & Prevention, 27, 1083-1090 (2018). 

22. Wenzel, A. G., Bloom, M. S., Butts, C. D., Wineland, R. J., Brock, J. W., Cruze, L., Unal, E. R., Kucklick, J. R., Somerville, S. E., and Newman, R. B., "Influence of race on prenatal phthalate exposure and anogenital measurements among boys and girls," Environment International, 110, 61-70 (2018). 

23. Wenzel, A. G., Brock, J. W., Cruze, L., Newman, R. B., Unal, E. R., Wolf, B. J., Somerville, S. E., and Kucklick, J. R., "Prevalence and predictors of phthalate exposure in pregnant women in Charleston, SC," Chemosphere, 193, 394-402 (2018). 

24. Wise, S. A., Phinney, K. W., Duewer, D. L., Sniegoski, L. T., Welch, M. J., Pritchett, J., Pabello, G., Calderon, M. A. A., Balderas, M., Liu, Q. D., Kooi, L. T., Rego, E., Garrido, B., Allegri, G., de La Cruz, M., Barrabin, J., Monteiro, T., Lee, H., Kim, B., Delatour, V., Peignaux, M., Kawaguchi, M., Bei, X., Can, Q., Nammoonnoy, J., Schild, K., Ohlendorf, R., Henrion, A., Goren, A. C., Yilmaz, H., Bilsel, M., Konopelko, L., Krylov, A., and Lopushanskaya, E., "CCQM-K11.2 Determination of Glucose in Human Serum and CCQM-K12.2 Determination of Creatinine in Human Serum," Metrologia, 55, (2018). 

25. Wise, S. A., Phinney, K. W., Duewer, D. L., Sniegoski, L. T., Welch, M. J., Pabello, G., Caldero, M. A. A., Liu, Q. D., Kooi, L. T., Rego, E., Garrido, B., Allegri, G., de La Cruz, M., Barrabin, J., Puglisi, C., Lopez, E., Lee, H., Kim, B., Delatour, V., Heuillet, M., Nammoonnoy, J., Goren, A. C., Bilsel, G., Konopelko, L., Krylov, A., and Lopushanskaya, E., "CCQM-K6.2 Determination of Total Cholesterol in Human Serum," Metrologia, 55, (2018). 

26. Abad, S. Q., Rodriguez-Gonzalez, P., Davis, W. C., and Alonso, J. I. G., "Development of a Common Procedure for the Determination of Methylmercury, Ethylmercury, and Inorganic Mercury in Human Whole Blood, Hair, and Urine by Triple Spike Species-Specific Isotope Dilution Mass Spectrometry," Analytical Chemistry, 89 , 6731-6739 (2017). 

27. Bowden, J. A., Heckert, A., Ulmer, C. Z., Jones, C. M., Koelmel, J. P., Abdullah, L., Ahonen, L., Alnouti, Y., Armando, A. M., Asara, J. M., Bamba, T., Barr, J. R., Bergquist, J., Borchers, C. H., Brandsma, J., Breitkopf, S. B., Cajka, T., Cazenave-Gassiot, A., Checa, A., Cinel, M. A., Colas, R. A., Cremers, S., Dennis, E. A., Evans, J. E., Fauland, A., Fiehn, O., Gardner, M. S., Garrett, T. J., Gotlinger, K. H., Han, J., Huang, Y. Y., Neo, A. H. P., Hyotylainen, T., Izumi, Y., Jiang, H. F., Jiang, H. L., Jiang, J., Kachman, M., Kiyonami, R., Klavins, K., Klose, C., Kofeler, H. C., Kolmert, J., Koal, T., Koster, G., Kuklenyik, Z., Kurland, I. J., Leadley, M., Lin, K., Maddipati, K. R., McDougall, D., Meikle, P. J., Mellett, N. A., Monnin, C., Moseley, M. A., Nandakumar, R., Oresic, M., Patterson, R., Peake, D., Pierce, J. S., Post, M., Postle, A. D., Pugh, R., Qiu, Y. P., Quehenberger, O., Ramrup, P., Rees, J., Rembiesa, B., Reynaud, D., Roth, M. R., Sales, S., Schuhmann, K., Schwartzman, M. L., Serhan, C. N., Shevchenko, A., Somerville, S. E., John-Williams, L. S., Surma, M. A., Takeda, H., Thakare, R., Thompson, J. W., Torta, F., Triebl, A., Trotzmuller, M., Ubhayasekera, S. J. K., Vuckovic, D., Weir, J. M., Welti, R., Wenk, M. R., Wheelock, C. E., Yao, L. B., Yuan, M., Zhao, X. Q. H., and Zhou, S. L., "Harmonizing lipidomics: NIST interlaboratory comparison exercise for lipidomics using SRM 1950-Metabolites in Frozen Human Plasma," Journal of Lipid Research, 58, 2275-2288 (2017). 

28. Mccoy, J. A., Bangma, J. T., Reiner, J. L., Bowden, J. A., Schnorr, J., Slowey, M., O'Leary, T., Guillette, L. J., and Parrott, B. B., "Associations between perfluorinated alkyl acids in blood and ovarian follicular fluid and ovarian function in women undergoing assisted reproductive treatment," Science of the Total Environment, 605, 9-17 (2017). 

29. Moller, C., Davis, W. C., Thompson, V. R., Mari, F., and DeCaprio, A. P., "Proteomic Analysis of Thiol Modifications and Assessment of Structural Changes in Hemoglobin Induced by the Aniline Metabolites N-Phenylhydroxylamine and Nitrosobenzene," Scientific Reports, 7, (2017). 

30. Phinney, K. W., Camara, J. E., Tai, S. S. C., Sander, L. C., Wise, S. A., De Grande, L. A. C., Thienpont, L. M., Possolo, A. M., Toman, B., Sempos, C. T., Betz, J. M., and Coates, P. M., "Value Assignment of Vitamin D Metabolites in Vitamin D Standardization Program Serum Samples," Journal of Aoac International, 100, 1253-1259 (2017). 

31. Phinney, K. W., Tai, S. S. C., Bedner, M., Camara, J. E., Chia, R. R. C., Sander, L. C., Sharpless, K. E., Wise, S. A., Yen, J. H., Schleicher, R. L., Chaudhary-Webb, M., Maw, K. L., Rahmani, Y., Betz, J. M., Merkel, J., Sempos, C. T., Coates, P. M., Durazo-Arvizu, R. A., Sarafin, K., and Brooks, S. P. J., "Development of an Improved Standard Reference Material for Vitamin D Metabolites in Human Serum," Analytical Chemistry, 89, 4907-4913 (2017). 

32. Phinney, K. W., Sempos, C. T., Tai, S. S. C., Camara, J. E., Wise, S. A., Eckfeldt, J. H., Hoofnagle, A. N., Carter, G. D., Jones, J., Myers, G. L., Durazo-Arvizu, R., Miller, W. G., Bachmann, L. M., Young, I. S., Pettit, J., Caldwell, G., Liu, A., Brooks, S. P. J., Sarafin, K., Thamm, M., Mensink, G. S. M., Busch, M., Rabenberg, M., Cashman, K. D., Kiely, M., Galvin, K., Zhang, J. Y., Kinsella, M., Oh, K., Lee, S. W., Jung, C. L., Cox, L., Goldberg, G., Guberg, K., Meadows, S., and Prentice, A., "Baseline Assessment of 25-Hydroxyvitamin B Reference Material and Proficiency Testing/External Quality Assurance Material Commutability: A Vitamin B Standardization Program Study," Journal of Aoac International, 100, 1288-1293 (2017). 

33. Sheen, D., Rocha, W. F. D., Bearden, D., and Lippa, K., "Data harmonization and quality assurance in metabolomics for biological pathway identification," Abstracts of Papers of the American Chemical Society, 254, (2017). 

34. Tai, S. S. C., Nelson, M. A., Bedner, M., Lang, B. E., Phinney, K. W., Sander, L. C., Yen, J. H., Betz, J. M., Sempos, C. T., and Wise, S. A., "Development of Standard Reference Material (SRM) 2973 Vitamin D Metabolites in Frozen Human Serum (High Level)," Journal of Aoac International, 100, 1294-1303 (2017). 

35. Ulmer, C. Z., Ragland, J. M., Koelmel, J. P., Heckert, A., Jones, C. M., Garrett, T. J., Yost, R. A., and Bowden, J. A., "LipidQC: Method Validation Tool for Visual Comparison to SRM 1950 Using NIST Interlaboratory Comparison Exercise Lipid Consensus Mean Estimate Values," Analytical Chemistry, 89, 13069-13073 (2017). 

36. Wise, S. A., Tai, S. S. C., Duewer, D. L., Bedner, M., Camara, J. E., Lippa, K. A., Qinde, L., Kang, D., Kim, B., and Quan, C., "CCQM-K132: low-polarity analytes in a biological matrix: vitamin D metabolites in human serum," Metrologia, 54, (2017). 

37. Wise, S. A., Tai, S. S. C., Nelson, M. A., Burdette, C. Q., Camara, J. E., Hoofnagle, A. N., Laha, T. J., Carter, G. D., Jones, J., Williams, E. L., Barclay, Z. J., Jones, G., Kaufmann, M., Binkley, N., Kapoor, A., Ziegler, T., Cashman, K. D., Dowling, K. G., and Sempos, C. T., "Interlaboratory Comparison for the Determination of 24,25-Dihydroxyvitamin D-3 in Human Serum Using Liquid Chromatography with Tandem Mass Spectrometry," Journal of Aoac International, 100, 1308-1317 (2017). 

38. Wise, S. A., Phinney, K. W., Tai, S. S. C., Camara, J. E., Myers, G. L., Durazo-Arvizu, R., Tian, L., Hoofnagle, A. N., Bachmann, L. M., Young, I. S., Pettit, J., Caldwell, G., Liu, A., Brooks, S. P. J., Sarafin, K., Thamm, M., Mensink, G. B. M., Busch, M., Rabenberg, M., Cashman, K. D., Kiely, M., Kinsella, M., Galvin, K., Zhang, J. Y., Oh, K., Lee, S. W., Jung, C. L., Cox, L., Goldberg, G., Guberg, K., Prentice, A., Carter, G. D., Jones, J., Brannon, P. M., Lucas, R. M., Crump, P. M., Cavalier, E., Merkel, J., Betz, J. M., and Sempos, C. T., "Baseline Assessment of 25-Hydroxyvitamin D Assay Performance: A Vitamin D Standardization Program (ASP) Interlaboratory Comparison Study," Journal of Aoac International, 100, 1244-1252 (2017). 

39. Wise, S. A., Tai, S. S. C., Burdette, C. Q., Camara, J. E., Bedner, M., Lippa, K. A., Nelson, M. A., Nalin, F., Phinney, K. W., Sander, L. C., Betz, J. M., Sempos, C. T., and Coates, P. M., "Role of the National Institute of Standards and Technology (NIST) in Support of the Vitamin D Initiative of the National Institutes of Health, Office of Dietary Supplements," Journal of Aoac International, 100, 1260-1276 (2017). 

40. Roberts, D. R., Lindhorst, S. M., Welsh, C. T., Maravilla, K. R., Herring, M. N., Braun, K. A., Thiers, B. H., and Davis, W. C., "High Levels of Gadolinium Deposition in the Skin of a Patient With Normal Renal Function," Investigative Radiology,  51, 280-289 (2016). 

41. Schantz, M. M., Powers, C. D., Schleicher, R. L., Betz, J. M., and Wise, S. A., "Interlaboratory analytical comparison of fatty acid concentrations in serum or plasma," Clinica Chimica Acta, 462, 148-152 (2016). 

42. Bedner, M. and Lippa, K. A., "25-Hydroxyvitamin D isomerizes to pre-25-hydroxyvitamin D in solution: considerations for calibration in clinical measurements," Analytical and Bioanalytical Chemistry, 407, 8079-8086 (2015). 

43. Litorja, M., Urbas, A., and Zong, Y.,  "Radiometric calibration to consider in quantitative clinical fluorescence imaging measurements," Molecular-Guided Surgery: Molecules, Devices, and Applications, 9311, (2015). 

44. Nelson, M. A., Bedner, M., Lang, B. E., Toman, B., and Lippa, K. A., "Metrological approaches to organic chemical purity: primary reference materials for vitamin D metabolites," Analytical and Bioanalytical Chemistry, 407, 8557-8569 (2015). 

45. Schantz, M. M., Benner, B. A., Heckert, N. A., Sander, L. C., Sharpless, K. E., Vander Pol, S. S., Vasquez, Y., Villegas, M., Wise, S. A., Alwis, K. U., Blount, B. C., Calafat, A. M., Li, Z., Silva, M. J., Ye, X., Gaudreau, E., Patterson, D. G., and Sjodin, A., "Development of urine standard reference materials for metabolites of organic chemicals including polycyclic aromatic hydrocarbons, phthalates, phenols, parabens, and volatile organic compounds," Analytical and Bioanalytical Chemistry, 407, 2945-2954 (2015). 

46. Tai, S. S. C. and Nelson, M. A., "Candidate Reference Measurement Procedure for the Determination of (24R),25-Dihydroxyvitamin D3 in Human Serum Using Isotope-Dilution Liquid Chromatography-Tandem Mass Spectrometry," Analytical Chemistry, 87, 7964-7970 (2015). 

47. Bowden, J. A., Bangma, J. T., and Kucklick, J. R., "Development of an Automated Multi-Injection Shotgun Lipidomics Approach Using a Triple Quadrupole Mass Spectrometer," Lipids, 49, 609-619 (2014). 

48. Ordonez, Y. N., Anton, R. F., and Davis, W. C., "Quantification of total serum transferrin and transferrin sialoforms in human serum; an alternative method for the determination of carbohydrate-deficient transferrin in clinical samples," Analytical Methods, 6, 3967-3974 (2014). 

49. Paul, R. L., Davis, W. C., Yu, L., Murphy, K. E., Guthrie, W. F., Leber, D. D., Bryan, C. E., Vetter, T. W., Shakirova, G., Mitchell, G., Kyle, D. J., Jarrett, J. M., Caldwell, K. L., Jones, R. L., Eckdahl, S., Wermers, M., Maras, M., Palmer, C. D., Verostek, M. F., Geraghty, C. M., Steuerwald, A. J., and Parsons, P. J., "Certification of total arsenic in blood and urine standard reference materials by radiochemical neutron activation analysis and inductively coupled plasma-mass spectrometry," Journal of Radioanalytical and Nuclear Chemistry, 299, 1555-1563 (2014). 

50. Bedner, M., Lippa, K. A., and Tai, S. S. C., "An assessment of 25-hydroxyvitamin D measurements in comparability studies conducted by the Vitamin D Metabolites Quality Assurance Program," Clinica Chimica Acta, 426, 6-11 (2013). 

51. Camara, J. E., Duewer, D. L., Gasca-Aragon, H., Lippa, K. A., and Toman, B., "CCQM-K80 Comparison of value-assigned CRMs and PT materials: creatinine in human serum Final Report," Metrologia, 50, (2013). 

52. Phinney, K. W., Ballihaut, G., Bedner, M., Benford, B. S., Camara, J. E., Christopher, S. J., Davis, W. C., Dodder, N. G., Eppe, G., Lang, B. E., Long, S. E., Lowenthal, M. S., Mcgaw, E. A., Murphy, K. E., Nelson, B. C., Prendergast, J. L., Reiner, J. L., Rimmer, C. A., Sander, L. C., Schantz, M. M., Sharpless, K. E., Sniegoski, L. T., Tai, S. S. C., Thomas, J. B., Vetter, T. W., Welch, M. J., Wise, S. A., Wood, L. J., Guthrie, W. F., Hagwood, C. R., Leigh, S. D., Yen, J. H., Zhang, N. F., Chaudhary-Webb, M., Chen, H. P., Fazili, Z., Lavoie, D. J., Mccoy, L. F., Momin, S. S., Paladugula, N., Pendergrast, E. C., Pfeiffer, C. M., Powers, C. D., Rabinowitz, D., Rybak, M. E., Schleicher, R. L., Toombs, B. M. H., Xu, M., Zhang, M., and Castle, A. L., "Development of a Standard Reference Material for Metabolomics Research," Analytical Chemistry, 85, 11732-11738 (2013). 

53. Sander, L. C., Bedner, M., Duewer, D. L., Lippa, K. A., Phillips, M. M., Phinney, K. W., Rimmer, C. A., Schantz, M. M., Sharpless, K. E., Tai, S. S. C., Thomas, J. B., Wise, S. A., Wood, L. J., Betz, J. M., and Coates, P. M., "The development and implementation of quality assurance programs to support nutritional measurements," Analytical and Bioanalytical Chemistry, 405, 4437-4441 (2013). 

54. Schantz, M. M., Eppe, G., Focant, J. F., Hamilton, C., Heckert, N. A., Heltsley, R. M., Hoover, D., Keller, J. M., Leigh, S. D., Patterson, D. G., Pintar, A. L., Sharpless, K. E., Sjodin, A., Turner, W. E., Vander Pol, S. S., and Wise, S. A., "Milk and serum standard reference materials for monitoring organic contaminants in human samples," Analytical and Bioanalytical Chemistry, 405, 1203-1211 (2013). 

55. Simon-Manso, Y., Lowenthal, M. S., Kilpatrick, L. E., Sampson, M. L., Telu, K. H., Rudnick, P. A., Mallard, W. G., Bearden, D. W., Schock, T. B., Tchekhovskoi, D. V., Blonder, N., Yan, X. J., Liang, Y. X., Zheng, Y. F., Wallace, W. E., Neta, P., Phinney, K. W., Remaley, A. T., and Stein, S. E., "Metabolite Profiling of a NIST Standard Reference Material for Human Plasma (SRM 1950): GC-MS, LC-MS, NMR, and Clinical Laboratory Analyses, Libraries, and Web-Based Resources," Analytical Chemistry, 85, 11725-11731 (2013). 

56. Yu, L. L., Davis, W. C., Ordonez, Y. N., and Long, S. E., "Fast and accurate determination of K, Ca, and Mg in human serum by sector field ICP-MS," Analytical and Bioanalytical Chemistry, 405, 8761-8768 (2013). 

57. Ballihaut, G., Kilpatrick, L. E., Kilpatrick, E. L., and Davis, W. C., "Multiple forms of selenoprotein P in a candidate human plasma standard reference material," Metallomics, 4, 533-538 (2012). 

58. Bedner, M. and Phinney, K. W., "Development and comparison of three liquid chromatography-atmospheric pressure chemical ionization/mass spectrometry methods for determining vitamin D metabolites in human serum," Journal of Chromatography A, 1240, 132-139 (2012). 

59. Camara, J. E., Lippa, K. A., Duewer, D. L., Gasca-Aragon, H., and Toman, B., "An international assessment of the metrological equivalence of higher-order measurement services for creatinine in serum," Analytical and Bioanalytical Chemistry, 403, 527-535 (2012). 

60. Thomas, J. B., Duewer, D. L., Mugenya, I. O., Phinney, K. W., Sander, L. C., Sharpless, K. E., Sniegoski, L. T., Tai, S. S., Welch, M. J., and Yen, J. H., "Preparation and value assignment of standard reference material 968e fat-soluble vitamins, carotenoids, and cholesterol in human serum," Analytical and Bioanalytical Chemistry, 402, 749-762 (2012). 

61. Yu, L. L., Jarrett, J. M., Davis, W. C., Kilpatrick, E. L., Oflaz, R., Turk, G. C., Leber, D. D., Valentin, L., Morel-Espinosa, M., and Blount, B. C., "Characterization of perchlorate in a new frozen human urine standard reference material," Analytical and Bioanalytical Chemistry, 404, 1877-1886 (2012). 

62. Ballihaut, G., Kilpatrick, L. E., Kilpatrick, E. L., and Davis, W. C., "Detection and characterization of selenoproteins by tandem mass spectrometry assisted by laser ablation inductively coupled plasma mass spectrometry: application to human plasma selenoproteins," Journal of Analytical Atomic Spectrometry, 26 , 383-394 (2011). 

63. Ballihaut, G., Kilpatrick, L. E., and Davis, W. C., "Detection, Identification, and Quantification of Selenoproteins in a Candidate Human Plasma Standard Reference Material," Analytical Chemistry, 83, 8667-8674 (2011). 

64. Reiner, J. L., Phinney, K. W., and Keller, J. M., "Determination of perfluorinated compounds in human plasma and serum Standard Reference Materials using independent analytical methods," Analytical and Bioanalytical Chemistry, 401, 2899-2907 (2011). 

65. Yu, L. L., Verdon, C. P., Davis, W. C., Turk, G. C., Caldwell, K. L., Jones, R. L., Buckley, B., and Xie, R. M., "A human urine standard reference material for accurate assessment of arsenic exposure," Analytical Methods, 3, 1107-1115 (2011). 

66. Davis, W. C., Zeisler, R., Sieber, J. R., and Yu, L. L., "Methods for the separation and quantification of arsenic species in SRM 2669: arsenic species in frozen human urine," Analytical and Bioanalytical Chemistry, 396, 3041-3050 (2010). 

67. Rudnick, P. A., Clauser, K. R., Kilpatrick, L. E., Tchekhovskoi, D. V., Neta, P., Blonder, N., Billheimer, D. D., Blackman, R. K., Bunk, D. M., Cardasis, H. L., Ham, A. J. L., Jaffe, J. D., Kinsinger, C. R., Mesri, M., Neubert, T. A., Schilling, B., Tabb, D. L., Tegeler, T. J., Vega-Montoto, L., Variyath, A. M., Wang, M., Wang, P., Whiteaker, J. R., Zimmerman, L. J., Carr, S. A., Fisher, S. J., Gibson, B. W., Paulovich, A. G., Regnier, F. E., Rodriguez, H., Spiegelman, C., Tempst, P., Liebler, D. C., and Stein, S. E., "Performance Metrics for Liquid Chromatography-Tandem Mass Spectrometry Systems in Proteomics Analyses," Molecular & Cellular Proteomics, 9, 225-241 (2010). 

68. Stern, S. T., Hall, J. B., Yu, L. L., Wood, L. J., Paciotti, G. F., Tamarkin, L., Long, S. E., and Mcneil, S. E., "Translational considerations for cancer nanomedicine," Journal of Controlled Release, 146, 164-174 (2010). 

69. Tai, S. S. C., Bedner, M., and Phinney, K. W., "Development of a Candidate Reference Measurement Procedure for the Determination of 25-Hydroxyvitamin D-3 and 25-Hydroxyvitamin D-2 in Human Serum Using Isotope-Dilution Liquid Chromatography-Tandem Mass Spectrometry," Analytical Chemistry, 82, 1942-1948 (2010). 

70. Tai, S. S. C., Duewer, D. L., Urquiza, M. P., Lee, H., Mussell, C., Dai, X. H., Phinney, K. W., Welch, M. J., Wise, S. A., Murby, J., Kawaguchi, M., and Henrion, A., "Final report on CCQM-K63.a,b: Non-peptide hormones in serum: cortisol and progesterone," Metrologia, 47, (2010). 

71. Bedner, M., Phinney, K. W., and Sander, L. C., "Determination of vitamin D metabolites in serum using LC-MS and LC-MS/MS," Abstracts of Papers of the American Chemical Society, 237, 301 (2009). 

72. Kilpatrick, E. L., Liao, W., Turko, I. V., Camara, J. E., Dodder, N. G., and Bunk, D. M., "Quantification of C-reactive protein in human serum with affinity purification and isotope-dilution tandem mass spectrometry," Clinical Chemistry, 55, A205-A206 (2009). 

73. Nelson, B. C., Pfeiffer, C. M., Zhang, M., Duewer, D. L., Sharpless, K. E., and Lippa, K. A., "Commutability of NIST SRM 1955 Homocysteine and Folate in Frozen Human Serum with selected total homocysteine immunoassays and enzymatic assays," Clinica Chimica Acta, 395, 99-105 (2008). 

74. Camara, J. E. and Hays, F. A., "Discrimination between wild-type and ampicillin-resistant Escherichia coli by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry," Analytical and Bioanalytical Chemistry, 389, 1633-1638 (2007). 

75. Schantz, M. M., Keller, J. M., Leigh, S., Patterson, D. G., Sharpless, K. E., Sjodin, A., Stapleton, H. M., Swarthout, R., Turner, W. E., and Wise, S. A., "Certification of SRM 1589a PCBs, pesticides, PBDEs, and dioxins/furans in human serum," Analytical and Bioanalytical Chemistry, 389, 1201-1208 (2007). 

76. Murphy, K. E., Schantz, M. M., Butler, T. A., Benner, B. A., Wood, L. J., and Turk, G. C., "Determination of cyanide in blood by isotope-dilution gas chromatography-mass spectrometry," Clinical Chemistry, 52, 458-467 (2006). 

77. Christopher, S. J., Day, R. D., Bryan, C. E., and Turk, G. C., "Improved calibration strategy for measurement of trace elements in biological and clinical whole blood reference materials via collision-cell inductively coupled plasma mass spectrometry," Journal of Analytical Atomic Spectrometry, 20, 1035-1043 (2005). 

78. Turk, G. C., Duewer, D. L., Long, S. E., Burritt, M. F., and Butz, J. A., "Proposed process for a NIST traceable clinical reference laboratory network," Clinical Chemistry, 51, A200 (2005). 

79. Margolis, S. A., Vangel, M., and Duewer, D. L., "Certification of standard reference material 970, ascorbic acid in serum, and analysis of associated interlaboratory bias in the measurement process," Clinical Chemistry, 49, 463-469 (2003). 

80. Long, S. E. and Vetter, T. W., "Determination of sodium in blood serum by inductively coupled plasma mass spectrometry," Journal of Analytical Atomic Spectrometry, 17, 1589-1594 (2002). 

81. Thomas, J. B., Kline, M. C., Gill, L. M., Yen, J. H., Duewer, D. L., Sniegoski, L. T., and Sharpless, K. E., "Preparation and value assignment of standard reference material 968c fat-soluble vitamins, carotenoids, and cholesterol in human serum," Clinica Chimica Acta, 305, 141-155 (2001). 

82. Duewer, D. L., Kline, M. C., Sharpless, K. E., Thomas, J. B., Stacewicz-Sapuntzakis, M., and Sowell, A. L., "NIST Micronutrients Measurement Quality Assurance Program: Characterizing individual participant measurement performance over time," Analytical Chemistry, 72, 3611-3619 (2000). 

83. Duewer, D. L., Kline, M. C., Sharpless, K. E., and Thomas, J. B., "NIST micronutrients measurement quality assurance program: Characterizing the measurement community's performance over time," Analytical Chemistry, 72, 4163-4170 (2000). 

84. Duewer, D. L., Kline, M. C., Sharpless, K. E., Thomas, J. B., and Gary, K. T., "Micronutrients measurement quality assurance program: Helping participants use interlaboratory comparison exercise results to improve their long-term measurement performance," Analytical Chemistry, 71, 1870-1878 (1999). 

85. Dalluge, J. J. and Sander, L. C., "Precolumn affinity capillary electrophoresis for the identification of clinically relevant proteins in human serum: Application to human cardiac troponin I," Analytical Chemistry, 70, 5339-5343 (1998). 

86. Phinney, C. S., Murphy, K. E., Welch, M. J., Ellerbe, P. M., Long, S. E., Pratt, K. W., Schiller, S. B., Sniegoski, L. T., Rearick, M. S., Vetter, T. W., and Vocke, R. D., "Definitive method certification of clinical analytes in lyophilized human serum: NIST standard reference material (SRM) 909b," Fresenius Journal of Analytical Chemistry, 361, 71-80 (1998). 

87. Tai, S. S. C., Christensen, R. G., Sander, L. C., and Welch, M. J., "Certification of morphine-3-beta-D-glucoronide in a human urine standard reference material," Fresenius Journal of Analytical Chemistry, 357, 373-378 (1997). 

88. Margolis, S. A. and Duewer, D. L., "Measurement of ascorbic acid in human plasma and serum: Stability, intralaboratory repeatability, and interlaboratory reproducibility," Clinical Chemistry, 42, 1257-1262 (1996). 

89. Moody, J. R. and Vetter, T. W., "Development of the ion exchange-gravimetric method for sodium in serum as a definitive method," Journal of Research of the National Institute of Standards and Technology, 101, 155-164 (1996). 

90. Sharpless, K. E., Thomas, J. B., Sander, L. C., and Wise, S. A., "Liquid chromatographic determination of carotenoids in human serum using an engineered C-30 and a C-18 stationary phase," Journal of Chromatography B-Biomedical Applications, 678, 187-195 (1996). 

91. Thomas, J. B. R., Kline, M. C., Schiller, S. B., Ellerbe, P. M., Sniegoski, L. T., Duewer, D. L., and Sharpless, K. E., "Certification of fat soluble vitamins, carotenoids, and cholesterol in human serum: Standard reference material 968b," Fresenius Journal of Analytical Chemistry, 356, 1-9 (1996). 

92. Sharpless, K. S. and Duewer, D. L., "Population-Distributions and Intralaboratory Reproducibility for Fat-Soluble Vitamin Related-Compounds in Human Serum," Analytical Chemistry, 67, 4416-4422 (1995). 

93. Thomas, J. B., Sharpless, K. S., Kline, M. C., Sniegoski, L. T., Ellerbe, P. M., Schiller, S. B., and Wise, S. A., "Preparation and Certification of Standard Reference Material 968B - Fat-Soluble Vitamins and Cholesterol in Human Serum," Abstracts of Papers of the American Chemical Society, 210, 25-ANYL (1995).