Considerations of noise and measurement reproducibility of circular dichroism measurements using Na[Co III(EDDS)]

Abstract

Although circular dichroism (CD) spectroscopy has become ubiquitous in biological, chemical, and pharmacological laboratories, several issues with instrument calibration and standardization, measurements quality, and reproducibility still remain. In the context of validating and developing a wide-wavelength-range stable standard for CD that is available in both enantiomeric forms, (R,R)- and (S,S)-Na[Co III(EDDS)] (where EDDS is ethylenediaminedisuccinato), we have become aware of sources of error in CD spectroscopy in addition to instrument calibration and user issues. This article summarizes those errors and suggests procedures for minimizing them by averaging over sufficient independent data accumulations with appropriate parameters. Show more