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Monique Johnson

Dr. Monique E. Johnson, an analytical chemist, received her undergraduate degree in Chemistry from Lincoln University and her doctorate degree in Analytical Chemistry from The University of Massachusetts Amherst. She is presently a Research Chemist and postdoctoral fellow at the National Institute of Standards and Technology (NIST). Dr. Johnson's current research is an interdisciplinary project which explores the uptake of engineered nanomaterials in a model organism, Caenorhabditis elegans, where internalized nanomaterials are detected via conventional and single particle ICP-MS (inductively coupled plasma mass spectrometry), as well as TEM and confocal microscopy. As an analytical chemist, Monique has extensive experience in sample preparation of complex matrices such as human breast milk, plants, and food stuffs for total analysis, as well as ICP-MS and ICP-OES (optical emission spectrometry) analysis.

Professional Awards and Recognition:

  • MML Accolade for Postdoctoral Fellows for outstanding development and validation of a sucrose density gradient centrifugation method for the selective separation of C. elegans nematodes from engineered nanoparticles, 2015
  • NorthEast Alliance Graduate Fellow, 2007-2012
  • Nanotechnology IGERT Fellow, 2009-2011

Membership and Professional Activities:

  • American Chemical Society

Other Publications:


Determining what really counts: Modeling and measuring nanoparticle number concentrations

Elijah J. Petersen, Antonio R. Montoro Bustos, Blaza Toman, Monique E. Johnson, Mark Ellefson, George C. Caceres, Anna Lena Neuer, Qilin Chan, Jonathan Kemling, Brian Mader, Karen E. Murphy, Matthias Roesslein
Elijah J. Petersen, Antonio Montoro Bustos, Blaza Toman, Monique Johnson, Mark Ellefson, George C. Caceres, Anna Lena Neuer, Qilin Chan, Jonathan Kemling, Brian

Strategies for robust and accurate measurement of nanomaterial bioaccumulation

Elijah J. Petersen, Monika Mortimer, Robert Burgess, Richard Handy, Shannon Hanna, Kay Ho, Monique E. Johnson, Susana Louriero, Selck Henriette, Janeck Scott-Fordsmand, David Spurgeon, Jason Unrine, Nico van den Brink, Ying Wang, Jason White, Patricia Holden
One of the key components for environmental risk assessment of engineered nanomaterials (ENMs) is data on bioaccumulation potential. Accurately measuring

Agglomeration of Escherichia coli with positively charged nanoparticles can lead to artifacts in a standard Caenorhabditis elegans toxicity assay

Shannon Hanna, Antonio R. Montoro Bustos, Alexander W. Peterson, Vytautas Reipa, Leona D. Scanlan, Sanem Hosbas Coskun, Tae Joon Cho, Monique E. Johnson, Vincent A. Hackley, Bryant C. Nelson, Michael R. Winchester, John T. Elliott, Elijah J. Petersen
The increased use and incorporation of engineered nanoparticles (ENPs) in consumer products requires a robust assessment of their potential environmental

Counting Caenorhabditis elegans: Protocol Optimization and Applications for Population Growth and Toxicity Studies in Liquid Medium

Steven P. Lund, Sanem Hosbas Coskun, Monique E. Johnson, Christopher M. Sims, Elijah J. Petersen, John T. Elliott, Bryant C. Nelson, Leona D. Scanlan, Shannon K. Hanna, Karina Brignoni, Patricia Lapasett
The nematode Caenorhabditis elegans is used extensively in molecular, toxicological and genetics research. However, standardized methods for counting nematodes
Created October 9, 2019, Updated February 10, 2020