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The Metrology of Counting Protein Particles



Dean C. Ripple, Michael J. Carrier, Richard E. Cavicchi, Christopher B. Montgomery, Zhishang Hu


A common degradation pathway for protein-based drugs is the growth of protein aggregates or particles. Counting and characterization of these particles is needed to assure the quality, efficacy, and safety of this type of drug. The unusual physical attributes of protein particles lead to difficulties in obtaining accurate particle counts with traditional calibration standards and methods. We describe the development of instrument-response models, novel instrumentation, and novel reference materials to address this metrology issue.
Cal Lab: International Journal of Metrology


aggregate, light obscuration, microscopy, particle, pharmaceutical, protein, reference material


Ripple, D. , Carrier, M. , Cavicchi, R. , Montgomery, C. and Hu, Z. (2013), The Metrology of Counting Protein Particles, Cal Lab: International Journal of Metrology (Accessed May 29, 2024)


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Created July 13, 2013, Updated February 19, 2017