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Alexander Peterson (Fed)

Research Chemist

Research Interests:

My research interests are to help develop and add measurement confidence to modern microscopy techniques based on physical measurement microscopy, techniques that measure the intrinsic optical properties of cells in a live-cell, label-free, non-destructive format.  These intrinsic properties (refractive index, absorbance, scattering) are directly derived into cellular physical properties: mass, volume, density, and growth.  These are critical cell-based measurement needs!  These properties are traceable, derived from SI units, and amenable to the use of reference materials to aid in measurement reproducibility and comparability. 

Most microscopy strategies are observational and current technology relies on fundamentally qualitative techniques.   It cannot escape from human subjectivity.  

I am most interested in physical microscopy techniques such as surface plasmon resonance imaging, quantitative phase imaging, and enhanced darkfield imaging.  Basic research, clinical assays, and biomanufacturing industry need measurement techniques like these that are reproducible, quantitative and non-invasive.

Research Areas:


Physical Microscopy Properties and Techniques
Physical microscopy techniques allow for measurement of physical  properties and are amenable for reference material artifacts.
Credit: Alexander Peterson


Research Opportunities

2-year fellowship at NIST on the topic of:

Contact alexander.peterson [at] (Alexander Peterson) if interested in applying and writing a proposal (3000 words).  Application deadlines Feb. 1 and Aug. 1. Open to U.S. citizens, $74,950 stipend plus benefits, relocation expenses included.


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

Shannon Hanna, Antonio Montoro Bustos, Alexander W. Peterson, Vytas Reipa, Leona D. Scanlan, Sanem Hosbas Coskun, Tae Joon Cho, Monique Johnson, Vincent A. Hackley, Bryant C. Nelson, Michael R. Winchester, John T. Elliott, Elijah Petersen
The increased use and incorporation of engineered nanoparticles (ENPs) in consumer products requires a robust assessment of their potential environmental
Created October 9, 2019, Updated August 31, 2023