Method for detecting antioxidant degradation product in sodium chloride injection of levofloxacin lactate

The invention provides a method for detecting an antioxidant degradation product in a sodium chloride injection of levofloxacin lactate. The sodium chloride injection of levofloxacin lactate is treated by adopting solid-phase extraction, and the step of cleaning the levofloxacin lactate on a solid-phase extraction column by using an acetic acid solution with a specific concentration is added before elution, so that the interference of the levofloxacin lactate on the detection of 2, 4-di-tert-butylphenol and 3, 5-di-tert-butyl-4-hydroxyphenylpropionic acid is avoided; and then ACQUITY UPLC BEHC18 is adopted, an acetonitrile-aqueous solution with the volume ratio of 70: 30 is taken as a mobile phase, and detection is carried out under the detection wavelength of 280 nm. The method has the advantages of high sensitivity, accurate quantification and short detection time, and accurate and quantitative detection of 3, 5-di-tert-butyl-4-hydroxyphenylpropionic acid and 2, 4-di-tert-butylphenol in the sodium chloride