Estrone Injectable Suspension
» Estrone Injectable Suspension is a sterile suspension of Estrone in Water for Injection. It contains not less than 90.0 percent and not more than 115.0 percent of the labeled amount of C18H22O2.
Packaging and storage— Preserve in single-dose or in multiple-dose containers, preferably of Type I glass.
Identification— Transfer a volume of Injectable Suspension, equivalent to about 5 mg of estrone, to a glass-stoppered centrifuge tube, and add 2.5 mL of a mixture of ether and benzene (1:1). Shake for 2 minutes, and allow insoluble matter to settle, centrifuging, if necessary, to obtain a clear supernatant. Apply 5 µL each of this supernatant and a 1 in 500 solution of USP Estrone RS in a mixture of ether and benzene (1:1) to a suitable thin-layer chromatographic plate (see Chromatography 621), coated with a 0.25-mm layer of chromatographic silica gel. Allow the spots to dry, and develop the chromatogram in a solvent system consisting of a mixture of benzene and acetone (4:1) until the solvent front has moved about three-fourths of the length of the plate. Remove the plate from the developing chamber, mark the solvent front, and allow the solvent to evaporate. Spray the plate with a mixture of dehydrated alcohol and sulfuric acid (3:1), and heat in an oven at 105 for 10 minutes: the RF value and appearance (pale orange to amber by direct observation in daylight, and fluorescing pale yellow-green under long-wavelength UV light) of the principal spot obtained from the test solution correspond to those obtained from the Standard solution.
Bacterial endotoxins 85 It contains not more than 88.0 USP Endotoxin Units per mg of estrone.
Uniformity of dosage units 905: meets the requirements.
Other requirements— It meets the requirements under Injections 1.
Assay—
Mobile phase, Standard preparation, and Chromatographic system— Prepare as directed in the Assay under Estrone.
Assay preparation— Transfer an accurately measured volume of the well-mixed Injectable Suspension, equivalent to about 10 mg of estrone to a 50-mL volumetric flask. Add 30 mL of methanol and swirl for 5 minutes. Dilute with methanol to volume, and mix. Transfer 5.0 mL of this solution to a 25-mL volumetric flask, dilute with Mobile phase to volume, and mix.
Procedure— Proceed as directed for Procedure in the Assay under Estrone. Calculate the quantity, in mg, of C18H22O2 in each mL of Injectable Suspension taken by the formula:
0.25(C / V)(rU / rS)
in which V is the volume, in mL, of the Injectable Suspension taken, and the other terms are as defined therein.
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Topic/Question Contact Expert Committee
Monograph Daniel K. Bempong, Ph.D.
Senior Scientist
1-301-816-8143
(MDPS05) Monograph Development-Pulmonary and Steroids
Reference Standards Lili Wang, Technical Services Scientist
1-301-816-8129
RSTech@usp.org
85 Radhakrishna S Tirumalai, Ph.D.
Senior Scientist
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(MSA05) Microbiology and Sterility Assurance
USP32–NF27 Page 2314