Determination Of The Related Substances And The Content Of The Dextral-rabeprazole Sodium

R-rabeprazole Sodium,(R)-2-[[[4-(3-methoxypropoxy)-3-methyl-2-pyridyl]-methyl]sulfinyl]benzimidazole sodium,is one of the latest proton pump inhibitors.It can control the secretion of gastric acid by inhibiting the activity of H~+/K~+-ATPase,which was on the surface of the gastric parietal cell.It is proved that R-rabeprazole sodium has a stronger medicine activity than the S-isomer and raceme.Therefore,it is important to develop a novel process for preparing high purity R-rabeprazole sodium and high-efficiency method for controlling the quality of the target product.R-rabeprazole sodium was prepared via a new process by our group,and its structure was confirmed by using IR,1H-NMR,et.al.It is necessary to control the content of R-rabeprazole sodium and related substances strictly so as to ensure the quality of the target product.High Performance Liquid Chromatograp Hy(HPLC)was chosen to analysis their contents in this paper.The method for determination the contents of the related substances in R-rabeprazole sodium was as follows:the chromatograp Hic separation was achieved on YMC-Triart C18column(5μm,250 mm×4.6 mm),with a mobile p Hase of acetonitrile and p Hosp Hate buffer salt(p H 6.0)at rate of 1m L/min,analysed by a UV detector set at 285nm.In order to effectively separate R-rabeprazole and its related substances,gradient elution is a necessary choice.Under this condition,the calibration curve for each related substance is linear from0.04 to 1.11 g/m L and all the correlation coefficients are greater than 0.999.The recoveries measured by standard addition method at three different concentrations are all in the range of95.8%to123.2%.The limit of detection to each related substance is in the range of 2.58ng～73ng.The method for determination the content of R-rabeprazole sodium was as follows:YMC-Triart C18 column(5μm,250 mm×4.6 mm)was chosen as stationary p Hase,a mixed solution of p Hosp Hate buffer(p H 6.0)and acetonitrile with a 60/40 ratio(v/v)was used as the mobile p Hase,and UV detection at 285 nm was utilized.There is good linear relation between the peak area and concentration of R-rabeprazole sodium from 0.02mg/m L to 0.08mg/m L,the correlation coefficient R is 0.99997.Also,this method has good repeatability and high recovery.