IC determination of sodium bisulfite in dobutamine hydrochloride injection

Objective To establish a suppressed conductivity ion chromatography method for the determination of theantioxidant sodium bisulfite in dobutamine hydrochloride injection.Methods The IonPac AS11-HC(250 mm×4 mm,7 μm) was used as an ion analytical column with the eluent of 28.75 mmol·L-1 sodium hydroxide for the separation.The flow rate was 0.85 mL·min-1 and the suppressed conductivity detector was adopted.The diluted sample solution was mixed with 2 mL of trolamine and the mixture was filtered through a 0.45 μm syringem embrane before injection.Results This method exhibited excellent regression(r=0.999) at 5.09-35.69 μg·mL-1.The detection limit was 0.04 μg·mL-1.The average recovery was 98.1%(n=9).Conclusion The method is simple,accurate,sensible and reproducible,and can be used for the quality control of sodium bisulfite in dobutamine hydrochloride injection.