HPLC determination of the related substances Rotundine and Rotundine Sulfate Injection

Objective:An HPLC method for the testing of related substances in Rotundine and Rotundine Sulfate Injection was established.Method:The column:Agilent ZORBAX SB-C_(18)column(250 mm×4.6mm,5μm). The mobile phase:acetonitrile-phosphate buffer(pH 6.8)-triethylamine(60:40:1)(adjust its pH value to 6.8 by phosphoric acid).The detective wavelength:280 nm.The flow rate:1.0 mL·min~(-1).Result:The related sub- stance could be separated completely from Rotnndine.The lowest limit of detection was 1.2 ng.Conclusion:The method is simple,accurate and sensitive,and can be used for the determination of impurity in Rotundine and Ro- tundine Sulfate Injection.