|
|
BRIEFING
Sildenafil Citrate Oral Suspension. Because there is no existing USP monograph for this dosage form, a new monograph is proposed. The liquid chromatographic procedure in the Assay is based on analyses performed with a 3.0-mm × 15-cm column that contains 5-µm packing L1. USP has received data indicating that a Zorbax C18 column is suitable. The typical retention time for sildenafil citrate is about 7.1 min.
(CMP: R. Schnatz.)
Correspondence Number—C86200
Comment deadline: March 31, 2011
Add the following:
Sildenafil Citrate Oral Suspension
DEFINITION
Sildenafil Citrate Oral Suspension contains NLT 90.0% and NMT 110.0% of the labeled amount of sildenafil citrate (C22H30N6O4S·C6H8O7).
Prepare Sildenafil Citrate Oral Suspension 2.5 mg/mL as follows (see Pharmaceutical Compounding—Nonsterile Preparations 795):
Sildenafil Citrate 250 mg
Vehicle: a mixture of Vehicle for Oral Solution, NF, and Vehicle for Oral Suspension, NF (1:1), a sufficient quantity to make 100 mL
Calculate the required quantity of each ingredient for the total amount to be prepared. If using tablets, place the required number in a suitable mortar, and comminute to a fine powder with a pestle or use Sildenafil Citrate powder. Add the Vehicle in small portions and triturate to make a smooth paste. Add increasing volumes of the Vehicle to make a sildenafil citrate liquid that is pourable. Transfer the contents of the mortar, stepwise and quantitatively, to a calibrated bottle. Add enough of the Vehicle to bring to final volume, and mix well.
ASSAY
• Procedure
Mobile phase: Prepare a solution of 0.2 M ammonium acetate and acetonitrile (50:50). Pass through a nylon 66 filter of 0.45-µm pore size, and degas with helium.
Standard stock solution: 1.0 mg/mL of sildenafil citrate in methanol. [Note—The Standard solutions should be prepared from the appropriate reference material. ]
Standard solution: Pipet 1.0 mL of the Standard stock solution into a 10-mL volumetric flask, dilute with Mobile phase to volume to obtain a solution having a nominal concentration of 0.1 mg/mL of sildenafil citrate, and centrifuge.
Sample solution: Shake thoroughly by hand each bottle of Oral Suspension. Pipet 4.0 mL of Oral Suspension to a 10-mL volumetric flask, and dilute with methanol to volume. Pipet 1.0 mL of the diluted solution to a 10-mL volumetric flask, further dilute with Mobile phase to volume to obtain a solution with a nominal concentration of 0.1 mg/mL of sildenafil citrate, and centrifuge.
Chromatographic system
(See Chromatography 621, System Suitability.)
Mode: LC
Detector: UV 245 nm
Column: 3.0-mm × 15-cm; 5-µm packing L1
Column temperature: 25
Flow rate: 0.5 mL/min
Injection size: 10 µL
System suitability
Sample: Standard solution
[NOTE—The retention time for sildenafil citrate is about 7.1 min.]
Suitability requirements
Relative standard deviation: NMT 2.0% for replicate injections
Analysis
Samples: Standard solution and Sample solution
Calculate the percentage of the labeled amount of sildenafil citrate (C22H30N6O4S·C6H8O7) in the portion of Oral Suspension taken:
Result = (rU/rS) × (CS/CU) × 100
rU = peak response of the Sample solution
rS = peak response of the Standard solution
CS = concentration of sildenafil citrate in the Standard solution (µg/mL)
CU = nominal concentration of sildenafil citrate in the Sample solution (µg/mL)
Acceptance criteria: 90.0%–110.0%
SPECIFIC TESTS
• pH 791: 3.9–4.9
ADDITIONAL REQUIREMENTS
• Packaging and Storage: Package in tight, light-resistant containers. Store at controlled cold temperature or at controlled room temperature.
• Labeling: Label it to indicate that it is to be well-shaken before use, and to state the Beyond-Use Date.
• Beyond-Use Date: NMT 90 days after the date on which it was compounded, when stored at controlled cold temperature or controlled room temperatureUSP35
Auxiliary Information - Please check for your question in the FAQs before contacting USP. |
|
|手机版|药群论坛
( 蜀ICP备15007902号 )
收藏
支持
反对