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Joy Dunkers (Fed)

Physical Scientist

Microbial Community
Credit: Adobe Stock

Advanced Microscopy of Complex Microbial Communities

This project supports the Microbial Metrology program to advance microbiome community measurements and pathogen detection and identification. It uses advanced optical imaging methods and associated data analysis tools to address shortcomings in the quality, quantity or specificity of information acquired from conventional microbial methods to help answer the following critical questions: Who is there? Where are they? How many are there? What are they doing?

We are developing novel microbial microscopy techniques, software and measurements to advance the following projects:


Microbial Inactivation using Germicidal Ultraviolet Radiation

Germicidal UV in Healthcare
Credit: Adobe Stock

Germicidal ultraviolet (GUV) light, spanning 200 nm to 280 nm, has the potential to rapidly inactivate dangerous microbes. Until there are documentary standards and validated disinfection data, the marketplace is hesitant to make the necessary large capital investments for routine use of GUV in healthcare settings. We are contributing to the development of a documentary standard test method and the underpinning metrology for quantifying microbial inactivation using GUV. Once the method is validated, there will be a clearer path to GUV device acceptance in hospitals and clinics.

Research Opportunities

NIST-NRC Postdoctoral Research Associateship Program: 2-year fellowship at NIST, US citizens only, $74,750 salary plus benefits, travel stipend and relocation expenses. Requires 10 page research proposal plus additional materials. Contact me if interested in writing a microbial research proposal. Application deadlines are Feb. 1 and Aug. 1

Current opportunities available:


Mentoring Experience

Primary or co-advisor for 5 NRC postdocs

Advisor to 2 Montgomery College undergraduate students


Awards and Funding

Material Measurement Laboratory Collaboration and Teamwork Accolade for assisting the Office of Advanced Manufacturing as subject matter experts advising NIIMBL project teams funded through the CARES Act to respond to the pandemic national emergency, 2021

Co-champion of Innovations in Measurement Science Award for Shape Metrology Proposal, 2011-2013

Department of Commerce Gold Medal for Distinguished Achievement in Federal Service for Creating and Implementing Rigorous Testing Protocols and Benchmarks Needed to Ensure the Security and Integrity of the New US ePassport, 2007

Secured Phase I ($75k) and Phase II ($270k) of a Small Business Innovative Research award to develop a high speed dual channel imaging microscope for deep imaging of cells, tissue and tissue engineered constructs using optical coherence microscopy and two photon fluorescence, 2006-2008


Professional Organizations

American Society for Microbiology (National and DC Chapters)


Towards Absolute Viability Measurements for Bacteria

Joy Dunkers, Hariharan K. Iyer, Brynna H. Jones, Charles Camp, Stephan J. Stranick, Nancy Lin
Quantifying viable, vegetative bacteria is a critical measurand in healthcare diagnostics, food safety, and antimicrobial development. Viability determination
Created July 30, 2019, Updated February 3, 2023