Prednisone Oral Solution
»Prednisone Oral Solution contains not less than 90.0percent and not more than 110.0percent of the labeled amount of prednisone (C21H26O5).
Packaging and storage— Preserve in tight containers.
Identification— Shake 50mLof Oral Solution with 25mLof chloroform for 5minutes.Filter the chloroform extract through a pledget of cotton and a layer of anhydrous sodium sulfate,and evaporate on a warm water bath with the aid of a current of air to about 3mL.Continue the evaporation to dryness at room temperature.Wash the residue with two 10-mLportions of hot solvent hexane,decanting the solvent and discarding it each time.Digest the residue with 25mLof warm dehydrated alcohol for 15minutes.Filter the mixture,and evaporate the filtrate to about 3mL.Add solvent hexane until the mixture becomes slightly cloudy,and chill in a freezer to promote the formation of crystals.Collect the crystals,and dry at 60for 1hour:the crystals meet the requirements for Identificationtest Aunder Prednisone.
Add the following:
Uniformity of dosage units á905ñ—
FOR ORAL SOLUTION PACKAGED IN SINGLE-UNIT CONTAINERS: meets the requirements.USP28
Add the following:
Deliverable volume á698ñ—
FOR ORAL SOLUTION PACKAGED IN MULTIPLE-UNIT CONTAINERS: meets the requirements.USP28
pHá791ñ: between 2.6and 4.5.
Alcohol content,Method IIá611ñ: between 2.0%and 6.0%is found.
Assay—
Mobile phase— Dissolve 1.36g of monobasic potassium phosphate in 600mLof water,add 400mLof methanol,pass through a 0.2-µm membrane filter,and degas.Make adjustments if necessary (see System Suitabilityunder Chromatography á621ñ).
Standard preparation— Using an accurately weighed quantity of USP Prednisone RS,prepare a solution in alcohol containing 1mg per mL.Dilute 4volumes of this solution quantitatively with 96volumes of water to obtain a Standard preparationhaving a known concentration of about 40µg per mL.
Assay preparation— Transfer an accurately measured volume of Oral Solution,equivalent to about 10mg of prednisone,to a 250-mLvolumetric flask.Dilute with water to volume,and mix.
Chromatographic system(see Chromatography á621ñ)— The liquid chromatograph is equipped with a 254-nm detector and a 3.9-mm ×30-cm column that contains packing L1.The flow rate is about 1.5mLper minute.Chromatograph the Standard preparation,and record the peak responses as directed for Procedure:the tailing factor for the analyte peak is not more than 2.0;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 by means of a sampling valve,record the chromatograms,and measure the responses for the major peaks.Calculate the quantity,in mg,of prednisone (C21H26O5)in each mLof the Oral Solution taken by the formula:
(0.25C/V)(rU/rS),
in which Cis the concentration,in µg per mL,of USP Prednisone RSin the Standard preparation;Vis the volume,in mL,of Oral Solution taken;and rUand rSare the peak responses 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 1616
Pharmacopeial Forum:Volume No.30(1)Page 169
Phone Number:1-301-816-8139