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International Comparability in Circular Dichroism: II



Curtis W. Meuse, Jascindra Ravi, Paulina Rakowska, Tommaso Garfagnini, Alex E. Knight, Philippe Charlet, Julie D. Lorenz, Christopher Jones, David F. Plusquellic, Frank Wien, Liqing Wu


A previous inter-laboratory study, CCQM P59, showed that there was a poor level of comparability between laboratories in circular dichroism spectroscopy. In a follow-up study reported here, we achieved our goal of demonstrating improved comparability and data quality, primarily by addressing the problems identified in the previous study, which included cell path length measurement, instrument calibration and good practice in general. Multivariate analysis techniques (PCA and SIMCA) were shown to be useful in comparing large spectral data sets and in classifying spectra. However, our results also show that there is more work to be done to improve confidence in the technique as the discrepancies observed were partially due to systematic effects, which the statistical approaches do not consider. We therefore conclude that there is a need for an improved understanding of the uncertainties in CD measurement.


circular dichroism, international comparison, multivariate analysis, comparability, protein circular dichroism


Meuse, C. , Ravi, J. , Rakowska, P. , , T. , Knight, A. , , P. , D., J. , Jones, C. , Plusquellic, D. , Wien, F. and , L. (2010), International Comparability in Circular Dichroism: II, Metrologia, [online], (Accessed June 17, 2024)


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Created October 3, 2010, Updated November 18, 2020