Abstract
With HPLC using a diode array detector (DAD), a method of substitution for reference substances in impurity profiling control was developed that combined peak tracking by the correlation of spectra with application of correction factors for determination of each impurity. For qualitative analysis, two-dimensional (2D) standard spectrochromatographic data produced by HPLC-DAD were compared with sample data to develop 2D chromatographic spectral correlative maps so that the three target impurities were recognized without preparation and injection of reference solutions. For quantitative analysis, correction factors among cefonicid and the three impurities were established. The correction factors were 1.06 for 5-mercapto-1,2,3,4-tetrazole 1-methyl sulfonic acid detected at 255 nm, 0.77 for 7-aminocephalosporanic acid detected at 265 nm, and 0.97 for methoxycefonicid detected at 268 nm. The method could be used in analysis of related substances in cefonicid for injection without recourse to chemical reference standards of the three impurities.
EP-1510: Monte-Carlo determination of output correction factors for four detectors in small MV photon beams