Prednisolone
;)
Pregna-1,4-diene-3,20-dione,11,17,21-trihydroxy-,(11b)-.
11b,17,21-Trihydroxypregna-1,4-diene-3,20-dione (anhydrous) [50-24-8].
Sesquihydrate 387.48 [52438-85-4].
»Prednisolone is anhydrous or contains one and one-half molecules of water of hydration.It contains not less than 97.0percent and not more than 102.0percent of C21H28O5,calculated on the dried basis.
Packaging and storage—
Preserve in well-closed containers.
Labeling—
Label it to indicate whether it is anhydrous or hydrous.
Identification—
A:Infrared Absorption á197Kñ.
B:Ultraviolet Absorption á197Uñ—
Solution:
10µg per mL.
Medium:
methanol.
Absorptivities at 242nm,calculated on the dried basis,do not differ by more than 2.5%.If a difference appears,dissolve portions of both the test specimen and the Reference Standard in ethyl acetate,evaporate the solutions to dryness,and repeat the test on the residues.
Specific rotation á781Sñ:
between +97
and +103.
and +103.
Test solution:
10mg per mL,in dioxane.
Loss on drying á731ñ—
Dry it in vacuum at 105for 3hours:anhydrous Prednisolone loses not more than 1.0%,and hydrous Prednisolone not more than 7.0%,of its weight.
for 3hours:anhydrous Prednisolone loses not more than 1.0%,and hydrous Prednisolone not more than 7.0%,of its weight.
Residue on ignition á281ñ:
negligible,from 100mg.
Selenium á291ñ:
0.003%,a 200-mg test specimen being used.
Ordinary impurities á466ñ—
Solvent:
a mixture of alcohol and water (1:1).
Eluant:
a mixture of toluene and isopropyl alcohol (70:30),in a nonequilibrated chamber.
Visualization:
technique 1.
Assay—
Mobile phase—
Prepare a solution containing a mixture of butyl chloride,water-saturated butyl chloride,tetrahydrofuran,methanol,and glacial acetic acid (95:95:14:7:6).Make adjustments if necessary (see System Suitabilityunder Chromatography á621ñ).
Internal standard solution—
Prepare a solution of betamethasone in tetrahydrofuran containing 5mg per mL.Dilute this solution with water-saturated chloroform,and mix to obtain a solution having a final concentration of 0.5mg per mL.
Standard preparation—
Transfer about 10mg of USP Prednisolone RS,accurately weighed,to a 100-mLvolumetric flask,and dissolve in 5.0mLof methanol.Add 20.0mLof Internal standard solution,and mix.Dilute with water-saturated chloroform to 100.0mL,and mix.
Assay preparation—
Transfer about 10mg of Prednisolone,accurately weighed,to a 100-mLvolumetric flask,and dissolve in 5.0mLof methanol.Add 20.0mLof Internal standard solution,and mix.Dilute with water-saturated chloroform to 100.0mL,and mix.
Chromatographic system (see Chromatography á621ñ)—
The liquid chromatograph is equipped with a 254-nm detector and a 4-mm ×30-cm column that contains packing L3.The flow rate is about 1mLper minute.Chromatograph four replicate injections of the Standard preparation,and record the peak responses as directed for Procedure:the relative retention times are about 0.7for betamethasone and 1.0for prednisolone;the resolution,R,between prednisolone and betamethasone is not less than 3.5;and the relative standard deviation for replicate injections is not more than 2.0%.
Procedure—
Separately inject equal volumes (about 10µL)of the Standard preparationand the Assay preparationinto the chromatograph,record the chromatograms,and measure the responses for the major peaks.Calculate the quantity,in mg,of C21H28O5in the portion of Prednisolone taken by the formula:
0.1C(RU/RS),
in which Cis the concentration,in µg per mL,of USP Prednisolone RSin the Standard preparation;and RUand RSare the peak response ratios of prednisolone to the internal standard obtained from the Assay preparationand the Standard preparation,respectively.
Auxiliary Information—
Staff Liaison:Clydewyn M.Anthony,Ph.D.,Scientist
Expert Committee:(PA1)Pharmaceutical Analysis 1
USP28–NF23Page 1608
Pharmacopeial Forum:Volume No.30(5)Page 1641
Phone Number:1-301-816-8139