Postdoctoral Associate: Nanopore Spectroscopy for Single-Molecule Biodosimetry

Biophysical and Biomedical Measurement Group - NIST; United States; Vor Ort; USD 65.000 - 90.000; Vollzeit

Zusammenfassung

NIST's Biophysical and Biomedical Measurement Group in Gaithersburg, MD is seeking a postdoctoral research associate to develop nanopore spectroscopy measurements of radiation-induced damage to polymers and nucleic acids. The project extends work on biodosimetry using resistive-pulse nanopore measurements of DNA fragmentation.

Responsibilities include designing experiments, preparing samples, and analyzing ionizing-radiation dose effects as a function of radiation quality, LET, and dose rate,

Qualifikationen

• PhD in a relevant field as listed.
• Experience in nucleic acid chemistry, resistive-pulse sensing, nanopore spectroscopy, radiation chemistry or related areas.
• Strong experimental skills and ability to develop, troubleshoot, and validate measurement workflows.
• Strong data-analysis skills using Python, MATLAB, R or Origin.

Aufgaben

• Design and execute research on measuring ionizing-radiation dose using polymer chain scission reactions.
• Prepare and characterize polymers (e.g., cellulose) and nucleic acids (DNA/RNA) for irradiation and nanopore measurement.
• Measure radiation-induced molecular damage using nanopore spectroscopy and related single-molecule methods.
• Develop and validate dose-response curves vs. radiation quality (type, LET, dose rate).
• Analyze nanopore signals to quantify fragment-length distributions, damage, and uncertainty.
• Develop models linking radiation chemistry, molecular damage, absorbed dose, and RBE-related response.
• Collaborate with NIST teams in nanopore sensing, dosimetry, and biophysics.
• Report results through presentations and peer-reviewed publications.

Kenntnisse

Data analysis

Experiment design

Multidisciplinary collaboration

Communication skills

Scientific writing

Ausbildung

PhD in chemistry, biochemistry, biophysics, analytical chemistry, radiation chemistry, radiation biology, biomedical engineering, physics or closely related field

Tools

Python

MATLAB

R

Origin

Jobbeschreibung

The Biophysical and Biomedical Measurement Group at NIST (Gaithersburg, MD) is seeking a postdoctoral research associate to develop nanopore spectroscopy measurements of ionizing-radiation damage to polymers and nucleic acids.

This project builds on recent NIST work demonstrating single-molecule biodosimetry using resistive-pulse nanopore measurements of radiation‑induced DNA fragmentation. The next stage will expand this approach to quantify chain scission and molecular damage in standard polymers, including cellulose, and in nucleic acids such as DNA and RNA. Measurements will be performed as a function of absorbed dose and radiation quality, including radiation type, linear energy transfer (LET), dose rate, and related conditions.

The broader goal is to connect molecular damage to absorbed dose (Gy), radiation chemistry, and relative biological effectiveness (RBE), providing a complementary molecular measurement approach for radiation dosimetry, cancer‑therapy response assessment, and radiological emergency response.

This position is within the Biophysical Metrology and Inference program at NIST, which develops measurement approaches, physical models, and data‑analysis methods that connect biological signals to quantitative mechanism and uncertainty.

What you will do:

• Design and execute research on measuring ionizing‑radiation dose using polymer chain scission reactions.
• Prepare and characterize standard polymers (e.g., cellulose) and nucleic acids (DNA/RNA) for irradiation, nanopore measurement, and quantitative analysis.
• Measure radiation‑induced molecular damage using nanopore spectroscopy, resistive‑pulse sensing, nanopipettes, and related single‑molecule measurement approaches.
• Develop and validate dose‑response curves as a function of radiation quality, including radiation type, LET, dose rate, and related experimental conditions.
• Analyze nanopore signals to quantify fragment‑length distributions, chain scission, capture statistics, dose response, uncertainty, and reproducibility.
• Develop physical, statistical, and computational models linking radiation chemistry, direct/indirect molecular damage, absorbed dose (Gy), and RBE‑relevant response.
• Collaborate with NIST teams in nanopore sensing, radiation dosimetry, radiation biology/chemistry, and biophysical measurement.
• Report results through internal and external presentations and peer‑reviewed publications.

Required qualifications:

• Ph.D. in chemistry, biochemistry, biophysics, analytical chemistry, radiation chemistry, radiation biology, biomedical engineering, physics, or a closely related field.
• Demonstrated experience in one or more of the following: nucleic acid chemistry, resistive‑pulse sensing, nanopore spectroscopy, radiation chemistry, radiation biology, polymer/biopolymer damage, or single‑molecule measurement.
• Strong experimental skills and ability to develop, troubleshoot, and validate measurement workflows.
• Strong data‑analysis skills using Python, MATLAB, R, Origin, or similar tools.
• Strong written and oral communication skills.

Highly desired:

• Experience with nanopores, nanopipettes, ionic‑current measurements, resistive‑pulse sensing, electrophysiology, or electrochemical sensing.
• Experience with DNA/RNA sample preparation, nucleic‑acid damage assays, polymer chain scission, fragmentation analysis, or molecular‑length/molecular‑weight characterization.
• Experience with ionizing radiation, dosimetry, LET/radiation quality, radiation chemistry, radiation biology, RBE, or radiotherapy‑relevant measurements.
• Experience with statistical analysis, dose‑response modeling, signal processing, internal standards/calibration, and uncertainty quantification.
• Experience with spectroscopy, chromatography, electrophoresis, fluorescence methods, or complementary molecular characterization techniques.
• Ability to work effectively in a multidisciplinary environment spanning chemistry, biophysics, radiation science, nanopore measurement, and biomedical metrology.

U.S. citizenship is preferred; for some appointment mechanisms, eligibility depends on citizenship.

Group information:

https://www.nist.gov/pml/microsystems-and-nanotechnology-division/biophysical-and-biomedical-measurement-group

Related publication:

Single‑Molecule Biodosimetry

Analytical Chemistry 97, 22004-22012 (2025)

https://doi.org/10.1021/acs.analchem.5c03303

Related NIST story:

New Technique for Measuring DNA Damage Could Improve Cancer Therapy and Radiological Emergency Response

https://www.nist.gov/news-events/news/2025/08/new-technique-measuring-dna-damage-could-improve-cancer-therapy-and