(kloe bay' ta sol proe' pee oh nate).
Pregna-1,4-diene-3,20-dione, 21-chloro-9-fluoro-11-hydroxy-16-methyl-17-(1-oxopropoxy)-, (11,16)-;
21-Chloro-9-fluoro-11,17-dihydroxy-16-methylpregna-1,4-diene-3,20-dione 17-propionate [25122-46-7; 25122-41-2].
Clobetasol Propionate contains NLT 97.0% and NMT 102.0% of C25H32ClFO5, calculated on the dried basis.
Solution A: 0.05 M monobasic sodium phosphate. Adjust with 85% phosphoric acid to a pH of 2.5.
Mobile phase: Acetonitrile, methanol, and Solution A (19:4:17)
Internal standard solution: 0.2 mg/mL of beclomethasone dipropionate in methanol
Standard solution: Dissolve a quantity of USP Clobetasol Propionate RS in methanol and Internal standard solution to obtain a final solution of 0.04 mg/mL of USP Clobetasol Propionate RS and 0.08 mg/mL of beclomethasone dipropionate.
System suitability solution: 0.001 mg/mL of USP Clobetasol Propionate Related Compound A RS and 0.1 mg/mL of USP Clobetasol Propionate RS in Mobile phase
Sample solution: Transfer 4 mg of Clobetasol Propionate to a 100-mL volumetric flask, add 40.0 mL of Internal standard solution, and dilute with methanol to volume.
Detector: UV 240 nm
Column: 4.6-mm × 15-cm; packing L1
Flow rate: 1 mL/min
Injection size: 10 µL
Sample: System suitability solution
[NoteThe relative retention times for clobetasol propionate and clobetasol propionate related compound A are 1.0 and 1.1, respectively. ]
Resolution: NLT 1.5 between clobetasol propionate and clobetasol propionate related compound A
Column efficiency: NLT 5000 theoretical plates for the clobetasol peak
Tailing factor: NMT 2.0 for the clobetasol peak
Relative standard deviation: NMT 2.0%
Samples: Standard solution and Sample solution
[NoteThe relative retention times for clobetasol propionate and beclomethasone dipropionate are 1.0 and 1.6, respectively. ]
Calculate the percentage of C25H32ClFO5 in the portion of Clobetasol Propionate taken:
Result = (RU/RS) × (CS/CU) × 100
Acceptance criteria: 97.0%102.0% on the dried basis
• Residue on Ignition 281: NMT 0.1%, using a platinum crucible
• Heavy Metals, Method II 231: NMT 20 ppm
Solution A, Mobile phase, System suitability solution, and Chromatographic system: Proceed as directed in the Assay.
Sample solution: 0.1 mg/mL of Clobetasol Propionate in Mobile phase
Sample: Sample solution
Calculate the percentage of each impurity in the portion of Clobetasol Propionate taken:
Result = (rU/rT) × 100
Any individual impurity: NMT 1.0%
Total impurities: NMT 2.5%
• Melting Range or Temperature 741: Approximately 196
• Optical Rotation, Specific Rotation 781S: +98 to +104 at 20
Sample solution: 10 mg/mL in dioxane
• Loss on Drying 731: Dry a sample at 105 for 3 h: it loses NMT 2.0% of its weight.
• Packaging and Storage: Preserve in tight, light-resistant containers.
• USP Reference Standards 11
Auxiliary Information Please check for your question in the FAQs before contacting USP.
USP35NF30 Page 2713Pharmacopeial Forum: Volume No. 35(5) Page 1125