[Impurity profile study of cefalotin sodium by two-dimensional liquid chromatography-quadrupole time-of-flight mass spectrometry].

A two-dimensional liquid chromatography-quadrupole time-of-flight mass spectrometry (2D-LC-QTOF MS) method to profile the impurities of cefalotin sodium was developed. A Symmetry C18 column (250 mm x 4.6 mm, 5 μm) was used in the first dimensional chromatography, with gradient elution using pH 2.