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Published on: August 22, 2017
Determination of Relative Response Factors of Cefazolin Impurities by Quantitative NMR
Shuyu Liu1, Shangchen Yao2, Hailing Zhang1
1College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai, 201620, China.
Abstract:
The relative response factors (RRFs) of ten cefazolin impurities were determined by quantitative nuclear magnetic resonance (qNMR) and high-performance liquid chromatography (HPLC) equipped with an ultraviolet (UV) detector. The purities of these ten cefazolin impurities were successfully measured by qNMR for the purpose of RRFs determination by HPLC. The RRF values and their uncertainties determined by the two approaches are comparable. While the qNMR approach is effective and makes it easier to determine the RRFs for impurities, it also has the advantage of allowing the universal detection of protons without the limitations of common mass detectors. The use of qNMR provides a reliable and universal method for the RRF determination of impurities.
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