Dexpanthenol Preparation DEFINITION Dexpanthenol Preparation contains NLT 94.5% and NMT 98.5% of dexpanthenol (C9H19NO4), and NLT 2.7% and NMT 4.2% of pantolactone, both calculated on the anhydrous basis. IDENTIFICATION • A. The IR absorption spectrum of a thin film of Preparation exhibits maxima only at the same wavelengths as that of a similar preparation of USP Dexpanthenol RS, except that there is an additional maximum at 5.6 µm due to pantolactone. • B. Sample solution: 100 mg/mL of Preparation Analysis: To 1 mL of the Sample solution add 5 mL of 1 N sodium hydroxide and 1 drop of cupric sulfate TS, and shake vigorously. Acceptance criteria: A deep blue color develops. COMPOSITION • Content of Dexpanthenol 0.1 M potassium biphthalate: Transfer 20.42 g of potassium biphthalate into a 1000-mL volumetric flask, and add sufficient glacial acetic acid to dissolve. If necessary, warm the mixture on a steam bath to achieve complete solution, observing precautions against absorption of moisture. Cool to room temperature, and dilute with glacial acetic acid to volume. Sample: 400 mg of Preparation Blank: Proceed as directed in the Analysis, omitting the Sample. Titrimetric system (See Titrimetry 541.) Mode: Residual titration Titrant: 0.1 N perchloric acid VS Back-titrant: 0.1 M potassium biphthalate Endpoint detection: Visual Analysis: Transfer the Sample to a 300-mL flask fitted to a reflux condenser by means of a standard-taper glass joint, add 50.0 mL of Titrant, and reflux for 5 h. Cool, observing precautions to prevent atmospheric moisture from entering the condenser, and rinse the condenser with glacial acetic acid, collecting the rinsings in the flask. To the flask add 5 drops of crystal violet TS, and titrate with the Back-titrant to a blue-green endpoint. Perform the Blank determination. Calculate the percentage of dexpanthenol (C9H19NO4) in the Sample taken: Result = {[(VB VS) × M × F]/W} × 100
Acceptance criteria: 94.5%98.5% on the anhydrous basis • Content of Pantolactone Internal standard solution: 100 mg/mL of 2,6-dimethylphenol in toluene Standard stock solution: 10 mg/mL of USP Pantolactone RS in methylene chloride Standard solution: Pipet 0.4 mL of Standard stock solution into a suitable small vial. Evaporate the solvent by means of a steady stream of dry air, and add 50.0 µL of Internal standard solution. Add 1 mL of a mixture of pyridine, hexamethyldisilazane, and trimethylchlorosilane (9:3:1), immediately close the vial, and shake vigorously for 30 s. Sample solution: Transfer 100 mg of Preparation to a suitable small vial, and proceed as directed for the Standard solution, beginning with add 50.0 µL of Internal standard solution. Chromatographic system Mode: GC Detector: Flame ionization Column: 2.0-mm × 1.8-m, packed with 5% liquid phase G2 on support S1A Temperature Column: 170, isothermal Injector: 180 Flow rate: Using a suitable carrier gas, adjust the flow rate so that the derivatized pantolactone elutes in 4 min. Injection size: 0.5 µL System suitability Sample: Standard solution [NoteThe retention times of the derivatized pantolactone and derivatized internal standard are 0.75 and 1.0, respectively. ] Suitability requirements Resolution: NLT 2.0 between the derivatized pantolactone and derivatized internal standard Relative standard deviation: NMT 2.0% for the ratios of the derivatized pantolactone peak response to the derivatized internal standard peak response Analysis Samples: Standard solution and Sample solution Calculate the percentage of pantolactone in the portion of Preparation taken: Result = (RU/RS) × (V/W) × CS) × 100
Acceptance criteria: 2.7%4.2% on the anhydrous basis IMPURITIES • Residue on Ignition 281: NMT 0.1% • Limit of Aminopropanol Sample: 5 g of Preparation Blank: 10 mL of water Titrimetric system (See Titrimetry 541.) Mode: Direct titration Titrant: 0.1 N sulfuric acid VS Endpoint detection: Visual Analysis: Dissolve the Sample in 10 mL of water, and add bromothymol blue TS. Titrate with the Titrant to a yellow endpoint. Perform the Blank determination. Calculate the percentage of aminopropanol in the Sample taken: Result = {[(VS VB) × N × F]/W} × 100
Acceptance criteria: NMT 1.0% SPECIFIC TESTS • Optical Rotation, Specific Rotation 781S Sample solution: 50 mg/mL in water Acceptance criteria: +27.5 to +30.0 • Refractive Index 831: 1.4951.502, at 20 • Water Determination, Method I 921: NMT 1.0% ADDITIONAL REQUIREMENTS • Packaging and Storage: Preserve in tight containers. Auxiliary Information Please check for your question in the FAQs before contacting USP.
USP35NF30 Page 2850 Chromatographic Column Chromatographic columns text is not derived from, and not part of, USP 35 or NF 30. |