Stability Study of the Sample Solution Using for the Measurement of Related Substance in Raberprazole Sodium

Objective: To optimize the solvent system of sample solution for the measurement of related substances in raberprazole sodium in order to increase the stability of sample solution and the accuracy of measurement results. Methods: The influence of antioxygen quantity and solution pH on the solution stability were determined by factorial experiment to optimize the sample solution solvent system. Results: The dose of antioxygen and the pH of solution had synergistic influence on the stability of sample solution, but the influence of the pH of solution was greater. After optimization, the stability time prolonged to 4 h from 0.5 h(at room temperature of 20℃~30℃) which can guarantee the accurate measurement of related substances. The solvent system after optimization had no interference to the specificity of the measurement method. Conclusion: Resolving raberprazole sodium with the sulfite solution(resolving 7.56 g Na2 SO3 and 1.0 g NaOH in 1000 mL water)- acetonitrile(80∶20) can greatly improve the solution stability and meet the requirements of related substances measurement.