Niacin (nye' a sin). DEFINITION Niacin contains NLT 99.0% and NMT 101.0% of niacin (C6H5NO2), calculated on the dried basis. IDENTIFICATION • B. Ultraviolet Absorption 197U Wavelength range: 200300 nm Sample solution: 20 µg/mL in Buffer solution, prepared as directed in the Assay Acceptance criteria: Meets the requirements in the chapter. The A237/A262 ratio is 0.460.50. ASSAY • Procedure Buffer solution: Dissolve 6.8 g of monobasic potassium phosphate in 1000 mL of water. Adjust with 50% sodium hydroxide solution to a pH of 7.0. Standard solution: 0.02 mg/mL of USP Niacin RS in Buffer solution Sample solution: 0.02 mg/mL of Niacin in Buffer solution Blank: Buffer solution Instrumental conditions Mode: UV-Vis Analytical wavelength: 262 nm Cell: 1 cm Analysis Samples: Standard solution, Sample solution, and Blank Determine the absorbances of the solutions against the Blank. Calculate the percentage of niacin (C6H5NO2) in the portion of Niacin taken: Result = (AU/AS) × (CS/CU) × 100
Acceptance criteria: 99.0%101.0% on the dried basis IMPURITIES • Residue on Ignition 281: NMT 0.1% • Chloride and Sulfate, Chloride 221 Standard: 0.15 mL of 0.020 N hydrochloric acid Sample: 0.50 g of Niacin Acceptance criteria: NMT 0.02% • Chloride and Sulfate, Sulfate 221 Standard: 0.10 mL of 0.020 N sulfuric acid Sample: 0.50 g of Niacin Acceptance criteria: NMT 0.02% • Heavy Metals, Method I 231 Test preparation: Mix 1 g with 4 mL of 1 N acetic acid, and dilute with water to 25 mL. Heat gently until solution is complete, and cool. Acceptance criteria: NMT 20 ppm • Ordinary Impurities 466 Standard solutions and Test solution: Use water as the solvent. Eluant: A mixture of methanol and 0.1 N hydrochloric acid (9:1) Visualization: 1 Analysis: Proceed as directed in the chapter. Acceptance criteria: NMT 2.0% of total ordinary impurities SPECIFIC TESTS • Loss on Drying 731: Dry a sample at 105 for 1 h: it loses NMT 1.0% of its weight. ADDITIONAL REQUIREMENTS • Packaging and Storage: Preserve in well-closed containers. Auxiliary Information Please check for your question in the FAQs before contacting USP.
USP35NF30 Page 4042 Pharmacopeial Forum: Volume No. 29(6) Page 1937Chromatographic Column Chromatographic columns text is not derived from, and not part of, USP 35 or NF 30. |