Acetylcysteine (a seet'' il sis' teen). DEFINITION Acetylcysteine contains NLT 98.0% and NMT 102.0% of C5H9NO3S, calculated on the dried basis. IDENTIFICATION ASSAY • Procedure Mobile phase: 6.8 g/L of monobasic potassium phosphate. Adjust with phosphoric acid to a pH of 3.0. Sodium metabisulfite solution: 0.5 mg/mL of sodium metabisulfite in water, freshly prepared Internal standard solution: 5 mg/mL of USP l-Phenylalanine RS in Sodium metabisulfite solution Standard stock solution: 10 mg/mL of USP Acetylcysteine RS in Sodium metabisulfite solution Standard solution: 0.5 mg/mL of USP Acetylcysteine RS and 0.25 mg/mL of USP l-Phenylalanine RS in Sodium metabisulfite solution from Standard stock solution and Internal standard solution Sample stock solution: 10 mg/mL of Acetylcysteine in Sodium metabisulfite solution Sample solution: 0.5 mg/mL of Acetylcysteine and 0.25 mg/mL of USP l-Phenylalanine RS in Sodium metabisulfite solution from Sample stock solution and Internal standard solution Chromatographic system Mode: LC Detector: UV 214 nm Column: 3.9-mm × 30-cm; packing L1 Flow rate: 1.5 mL/min Injection size: 5 µL System suitability Sample: Standard solution [NoteThe relative retention times for acetylcysteine and l-phenylalanine are about 0.5 and 1.0, respectively. ] Suitability requirements Resolution: NLT 6 between acetylcysteine and l-phenylalanine Relative standard deviation: NMT 2.0% Analysis Samples: Standard solution and Sample solution Calculate the percentage of acetylcysteine (C5H9NO3S) in the portion of Acetylcysteine taken: Result = (RU/RS) × (CS/CU) × 100
Acceptance criteria: 98.0%102.0% on the dried basis IMPURITIES • Residue on Ignition 281: NMT 0.5% • Heavy Metals, Method II 231 [CautionExercise care because explosion may occur. ] Analysis: In a dropwise manner, wet the sample with 2 mL of nitric acid, and proceed as directed for the Test preparation. Acceptance criteria: NMT 10 ppm SPECIFIC TESTS • Optical Rotation, Specific Rotation 781S Buffer: Mix 29.5 mL of 1 N sodium hydroxide, 50 mL of 1 M monobasic potassium phosphate, and sufficient water to make 100 mL. Adjust to a pH of 7.0 ± 0.1 by adding more of either solution, as necessary. Sample solution: In a 25-mL volumetric flask, mix 1.25 g with 1 mL of edetate disodium solution (1 in 100), add 7.5 mL of sodium hydroxide solution (1 in 25), and mix to dissolve. Dilute with Buffer to volume. Acceptance criteria: +21 to +27 • pH 791: 2.02.8 in a solution (1 in 100) • Loss on Drying 731: Dry a sample at a pressure of about 50 mm of mercury at 70 for 4 h: it loses NMT 1.0% of its weight. ADDITIONAL REQUIREMENTS • Packaging and Storage: Preserve in tight containers, and store at controlled room temperature. Auxiliary Information Please check for your question in the FAQs before contacting USP.
USP35NF30 Page 2069 Pharmacopeial Forum: Volume No. 31(3) Page 726Chromatographic Column Chromatographic columns text is not derived from, and not part of, USP 35 or NF 30. |