Fluocinolone Acetonide Ointment
» Fluocinolone Acetonide Ointment contains not less than 90.0 percent and not more than 110.0 percent of the labeled amount of C24H30F2O6.
Packaging and storage— Preserve in collapsible tubes or tight containers.
USP Reference standards 11
USP Fluocinolone Acetonide RS Click to View Structure
USP Norethindrone RS Click to View Structure
Identification— Evaporate 10.0 mL of the Assay preparation obtained in the Assay to dryness, and dissolve the residue in 1 mL of chloroform: it responds to the Thin-layer Chromatographic Identification Test 201, 50 µL of the test solution and 50 µL of the Standard solution, containing about 50 µg per mL of USP Fluocinolone Acetonide RS, being applied and a mixture of chloroform and diethylamine (2:1) being used for development.
Microbial enumeration tests 61 and Tests for specified microorganisms 62 It meets the requirements of the tests for absence of Staphylococcus aureus and Pseudomonas aeruginosa.
Minimum fill 755: meets the requirements.
Assay—
Internal standard solution— Dissolve a suitable quantity of USP Norethindrone RS in methanol to obtain a solution containing about 850 µg per mL.
Diluted internal standard solution— Transfer 5.0 mL of Internal standard solution to a 250-mL flask. Dilute with methanol to volume, and mix.
Standard preparation— Dissolve an accurately weighed quantity of USP Fluocinolone Acetonide RS in acetonitrile to obtain a solution having a known concentration of about 200 µg per mL. Transfer 10.0 mL of this solution and 2.0 mL of Internal standard solution to a 100-mL volumetric flask. Dilute with methanol to volume, and mix. The concentration of USP Fluocinolone Acetonide RS in the Standard preparation is 20 µg per mL.
Mobile solvent— Prepare a mixture of acetonitrile and water (1:1). Adjust the ratio as necessary to obtain suitable chromatographic performance.
Assay preparation— Transfer an accurately weighed portion of Ointment, equivalent to about 0.7 mg of fluocinolone acetonide, to a 50-mL, round-bottom centrifuge tube. Add 35.0 mL of Diluted internal standard solution, emulsify using an ultrasonic probe, and centrifuge to bring the insoluble matter to the bottom. The clear supernatant is the Assay preparation.
Apparatus— Use a suitable high-pressure liquid chromatograph (see Chromatography 621) of the general type equipped with a detector for monitoring UV absorbance at about 254 nm, and capable of providing a flow rate of about 2 mL per minute for the Mobile solvent. Use a 50-cm × 4-mm column that contains packing L1 so as to provide a resolution factor, R (see Chromatography 621), of at least 2.0 between peaks for norethindrone and fluocinolone acetonide. Three replicate injections of the Standard preparation show a relative standard deviation of not more than 1.5%.
Procedure— Chromatograph equal volumes of the Assay preparation and the Standard preparation, adjusting the system as necessary to obtain peaks of between about 50% and 90% of full-scale. Calculate the quantity, in mg, of C24H30F2O6 in the portion of Ointment taken by the formula:
0.035C(RU / RS)
in which C is the concentration, in µg per mL, of USP Fluocinolone Acetonide RS in the Standard preparation; and RU and RS are the ratios of the peak areas of fluocinolone acetonide and the internal standard obtained from the Assay preparation and the Standard preparation, respectively.
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Topic/Question Contact Expert Committee
Monograph Domenick Vicchio, Ph.D.
Senior Scientific Liaison
1-301-998-6828
(SM42010) Monographs - Small Molecules 4
Reference Standards RS Technical Services
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61 Radhakrishna S Tirumalai, Ph.D.
Principal Scientific Liaison
1-301-816-8339
(GCM2010) General Chapters - Microbiology
62 Radhakrishna S Tirumalai, Ph.D.
Principal Scientific Liaison
1-301-816-8339
(GCM2010) General Chapters - Microbiology
USP35–NF30 Page 3226