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2019 Bronze Medal Award

Petersen, Elliott, Toman

Petersen, Elliott, Toman


The group is recognized for developing a strategy to improve bioassay reproducibility and demonstrating the strategy to assess nanomaterial toxicity. The toxicity assay design includes a novel test plate layout with in-process controls to monitor assay performance. The assay design was evaluated in an interlaboratory study with Europe, Switzerland, Thailand and South Korea and used to reveal and substantially reduce assay variability. The approach was adopted as an international standard in 2018 and has laid the foundation for the NIST measurement assurance program for cell-based assays.


John Elliott

Supervisory Physical Scientist
Material Measurement Laboratory

Elijah Petersen

Environmental Engineer
Material Measurement Laboratory

Blaza Toman

Mathematical Statistician
Material Measurement Laboratory