Aspartic Acid (as par' tik as' id). DEFINITION Aspartic Acid contains NLT 98.5% and NMT 101.5% of aspartic acid (C4H7NO4), calculated on the dried basis. IDENTIFICATION ASSAY • Procedure Sample: 100 mg of Aspartic Acid Titrimetric system (See Titrimetry 541.) Mode: Direct titration Titrant: 0.1 N sodium hydroxide VS Endpoint detection: Visual Blank: 50 mL of carbon dioxide-free water. Add 0.1 mL of bromothymol blue TS. Analysis: Transfer the Sample to a 125-mL flask, and dissolve in 50 mL of carbon dioxide-free water. Heat slightly if necessary. Cool, add 0.1 mL of bromothymol blue TS, and titrate with Titrant until the color changes from yellow to blue. Calculate the percentage of aspartic acid (C4H7NO4) in the portion of Aspartic Acid taken: Result = [(V B) × N × F × 100]/W
Acceptance criteria: 98.5%101.5% on the dried basis IMPURITIES • Residue on Ignition 281: NMT 0.1% • Chloride and Sulfate, Chloride 221 Sample solution: Dissolve 0.7 g of Aspartic Acid in 10 mL of diluted nitric acid, and dilute with water to 15 mL. Acceptance criteria: The Sample solution shows no more chloride than corresponds to 0.20 mL of 0.020 N hydrochloric acid (NMT 0.02%). • Chloride and Sulfate, Sulfate 221 Sample solution: Dissolve 0.8 g of Aspartic Acid in 4 mL of hydrochloric acid, and dilute with water to 15 mL. Acceptance criteria: The Sample solution shows no more sulfate than corresponds to 0.25 mL of 0.020 N sulfuric acid (NMT 0.03%). • Iron 241: NMT 10 ppm • Heavy Metals, Method II 231: NMT 10 ppm • Chromatographic Purity System suitability solution: 10 mg each of USP Aspartic Acid RS and glutamic acid in 2 mL of ammonia TS. Dilute with water to 25.0 mL. Standard solution: Transfer 5 mg of USP Aspartic Acid RS to a 100-mL volumetric flask, dissolve in 2 mL of 17% ammonia solution (prepared by diluting ammonium hydroxide, 6 in 10), and dilute with water to volume. Sample solution: Transfer 0.1 g of Aspartic Acid to a 10-mL volumetric flask, dissolve in 2 mL of 17% ammonia solution (prepared by diluting ammonium hydroxide, 6 in 10), and dilute with water to volume. Chromatographic system Mode: TLC Adsorbent: 0.25-mm layer of chromatographic silica gel mixture Application volume: 5 µL Developing solvent system: Butyl alcohol, glacial acetic acid, and water (3:1:1) Spray reagent: 2 mg/mL of ninhydrin in a mixture of butyl alcohol and 2 N acetic acid (95:5) System suitability Sample: System suitability solution Suitability requirement: The chromatogram of the System suitability solution exhibits two clearly separated spots. Analysis Samples: System suitability solution, Standard solution, and Sample solution Proceed as directed in the chapter, except dry the plate at 80 for 30 min, spray with Spray reagent, and heat at 80 for 30 min. Examine the plate under white light. Acceptance criteria: No secondary spot from the Sample solution is larger or more intense than the principal spot from the Standard solution. Individual impurities: NMT 0.5% Total impurities: NMT 2.0% SPECIFIC TESTS • Optical Rotation, Specific Rotation 781S Sample solution: 80 mg/mL in 6 N hydrochloric acid Acceptance criteria: +24.0 to +26.0, at 20 • Loss on Drying 731: Dry a sample at 105 for 3 h: it loses NMT 0.5% of its weight. ADDITIONAL REQUIREMENTS • Packaging and Storage: Preserve in well-closed containers, and store protected from light. Auxiliary Information Please check for your question in the FAQs before contacting USP.
USP35NF30 Page 2244 Pharmacopeial Forum: Volume No. 31(5) Page 1345 |