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William A MacCrehan (Assoc)

Bill's research started with the measurement of organometals (of mercury, tin, and lead) in biological and water in marine environmental samples. The determination of nitroaromatic compounds in air samples and phenolic compounds in crude and shale oil followed.  Methods for the measurement of fat soluble vitamins (E, K, and the isomers of A and β-carotene) in serum as well as the photoreactivity and electro-oxidation of retinol were another area of study. He was Co-PI for the first 3 years of the ongoing NCI-NIST Micronutrient Measurement Quality Assurance Program for these vitamins in sera. He has been quite interested in the chemistry and determination of reduced organic and inorganic compounds associated with marine water column and sediment anoxia. He was project manager for the investigation of the supercritical fluid extraction of environmental samples as part of the CSTL Consortium on Automated Analytical Systems (CAALS). For 20 years, he has done research into the forensic detection of gunshot and explosive residues from smokeless powder. The reactivity of wastewater components, including biological amines and pharmaceutical compounds with chlorine and chloramines has been an area of study. In the past 5 years, he has been the PI on a major Department of Homeland Security project to develop Standard Reference Materials and measurement technology for the detection of trace explosives including military and improvised compounds. The characterization, affinity, and impact of functionalized gold nanoparticles are also under current study. In all these activities, he has been interested in the development of novel liquid chromatographic and capillary electrophoretic separations as well as supercritical fluid and ultrasonic extractions. Detection approaches have included reductive and oxidative electrochemistry, post-column reaction chemistry, ultraviolet/visible absorbance, fluorescence, and mass spectrometric detection. He has 39 lead author and 31 coauthored publications.


  • ACS Undergraduate Achievement Award in Analytical Chemistry, 1972
  • Certificates of Recognition, Department of Commerce, 1981, 1983, 1985
  • Bronze Medal, Department of Commerce, 1995
  • Distinguished Service Award ASTM Committee E54, 2007

Membership and Professional Activities:

  • American Chemical Society
  • American Society for Testing and Materials, ASTM International, Committees E30 Forensic Sciences and E54 Homeland Security Applications (Task Chair)
  • Adjunct Professor, Department of Forensic Sciences, George Washington University, 1996-2003
  • Adjunct Professor, Department of Chemistry and Biochemistry, UMCP, 2000-01
  • Mentored 3 high school, 4 undergraduate, 14 graduate, 7 post-doctoral students and 2 guest scientists


NIST Micronutrients Measurement Quality Assurance Program: 1984-1985 Comparability Studies Results for Round Robins I, II, III and V Fat Soluble Vitamins and Carotenoids in Human Serum

Jeanice M. Brown Thomas, David L. Duewer, Margaret C. Kline, William A. MacCrehan, Robert Paule, Reenie Parris, Willie May, Robert Schaffer
From 1984 to 2017, the National Institute of Standards and Technology (NIST) and its precursor the National Burearu of Standards (NBS) coordinated what became

PEGylation of zinc nanoparticles amplifies their ability to enhance olfactory responses to odorant

Melissa Singletary, Samantha Hagerty, Shinichiro Muramoto, Yasmine Daniels, William A. MacCrehan, Gheorghe Stan, June W. Lau, Oleg Pustovyy, Ludmila Globa, Edward E. Morrison, Iryna Sorokulova, Vitaly Vodyanoy
Responses of olfactory sensory neurons to odorants are intensely enhanced with the addition of small endogenous and engineered zinc nanoparticles, as shown by
Created October 9, 2019, Updated December 8, 2022