Objective:To compare the quality differences in benzalkonium chloride samples from domestic and abroad to provide references for the quality standard revision for benzalkonium chloride in Chinese pharmacopoeia. Methods: The ratio of alkyl compo-nents was determined according to the method described in USP 38, and the total content of benzalkonium chloride was determined ac-cording to the method recorded in Chinese Pharmacopoeia (2015 edition) and USP 38, respectively. Results:According to the results of composition ratio of alkyl, the fraction defective of domestic samples and imported samples was 100% and 50%, respectively. The content difference between the values calculated by the methods in the two pharmacopoeias showed that the total content of domestic samples changed from 3. 86% to 4. 15%, and that of imported samples changed from 1. 15% to 3. 90%. Conclusion:There are sig-nificant differences in the quality of benzalkonium chloride between domestic samples and imported samples. It is recommended that the ratio of alkyl components should be supplemented in our pharmacopoeia referring to the method in USP 38 and the total content calcula-tion formula for benzalkonium chloride should be revised to improve the quality standard for benzalkonium chloride.

Objective:To determine the related substances in benzalkonium chloride used as a pharmaceutical adjuvant, and com-pare the quality at home and abroad. Methods:An HPLC method was used with an ODS-HYPERSIL C18 column(250 mm × 4. 6 mm, 5 μm). The detection wavelength was 210 nm and 257 nm. The flow rate was 1. 0 ml· min-1 and the column temperature was 30℃. The injection volume was 20 ml. The mobile phase was A ( dissolving 1. 09 g sodium1-hexanesulfonate and 6. 9 g sodium dihydrogen phosphate in water, adjusting pH to 3. 5 with phosphoric acid and diluting to 1 000. 0 ml) and B ( methanol) with gradient elution. Results:The content of benzaldehyde in the samples at home and abroad was low. The content of benzyl alcohol in the samples from a-broad was qualified, which was significantly higher than that in the domestic samples. The content of benzyl chloride in the domestic samples was higher than that in the samples from abroad. Conclusion:The method is simple and fast, which is suitable for comparing the related substances of domastic and imported samples. At the same time, the study provides basis for enterprises to choose benzalko-nium chloride rationally.