《埃索美拉唑镁usp34》.pdf

© 2010 USPC Official 5/1/11- ...页码，1/7 Esomeprazole Magnesium (es oh mep ra zole mag nee zee um). · C H MgN O S 3H O Trihydrate: 767.17 34 36 6 6 2 2 C H MgN O S Anhydrous: 713.12 34 36 6 6 2 1H-Benzimidazole,5-methoxy-2-[(S)-[(4-methoxy-3,5-dimethyl-2-pyridinyl)methyl]sulfinyl], magnesium salt (2:1), trihydrate; 5-Methoxy-2-[(S)-[(4-methoxy-3,5-dimethyl-2-pyridyl)methyl]sulfinyl]benzimidazole, magnesium salt (2:1), trihydrate [217087-09-7]. DEFINITION Esomeprazole Magnesium contains NLT 98.0% and NMT 102.0% of C H MgN O S , 34 36 6 6 2 calculated on the anhydrous basis. IDENTIFICATION • A. INFRARED ABSORPTION 197K • B. The Sample solution , prepared and tested as directed in the test for Content of Magnesium , exhibits a significant absorption at 285.2 nm. ASSAY • PROCEDURE Solution A: Dissolve 0.725 g of monobasic sodium phosphate and 4.472 g of anhydrous dibasic sodium phosphate in 300 mL of water, and dilute with water to 1000 mL. Dilute 250 mL of this solution with water to 1000 mL. If necessary, adjust with phosphoric acid to a pH of 7.6. Solution B: Mix 11 mL of 0.25 M tribasic sodium phosphate with 22 mL of 0.5 M dibasic sodium phosphate, and dilute with water to 100 mL. Mobile phase: Acetonitrile and Solution A (7:13) Standard solution: Transfer 10 mg of USP Omeprazole RS to a 200-mL volumetric flask, and dissolve in about 10 mL of methanol. Add 10 mL of Solution B, and dilute with water to volume. [NOTE—This solution contains 0.05 mg/mL of omeprazole. ] Sample solution: Transfer 10 mg of Esomeprazole Magnesium to a 200-mL volumetric flask, and dissolve in about 10 mL of m