Mesalamine Rectal Suspension
»Mesalamine Rectal Suspension is a suspension of Mesalamine in a suitable aqueous vehicle.It contains not less than 90.0percent and not more than 110.0percent of the labeled amount of mesalamine (C7H7NO3).It contains one or more suitable preservatives.
Packaging and storage— Preserve in tight,light-resistant containers.
Identification— The retention time of the major peak in the chromatogram of the Assay preparationcorresponds to that in the chromatogram of the Standard preparation,as obtained in the Assay.
Uniformity of dosage units á905ñ: meets the requirements.
PROCEDURE FOR CONTENT UNIFORMITY—
Buffer solution,Mobile phase,Resolution solution,and Chromatographic system— Proceed as directed in the Assayunder Mesalamine.
Standard solution— Transfer about 100mg of USP Mesalamine RS,accurately weighed,to a 50-mLvolumetric flask,add 15mLof 2Nhydrochloric acid,and dissolve by swirling.Dilute with 2Nhydrochloric acid to volume,and mix.Transfer 5.0mLof this solution to a 25-mLvolumetric flask,add 5mLof 2Nsodium hydroxide,dilute with Mobile phaseto volume,and mix.Pass this solution through a suitable filter having a 0.5-µm or finer porosity.
Test solution— Transfer,with the aid of 2Nhydrochloric acid,the contents of a container of Rectal Suspension to a 200-mLvolumetric flask.Add 2Nhydrochloric acid to obtain about 160mLof solution,and shake for about 10minutes.Dilute with 2Nhydrochloric acid to volume,and mix.Transfer an accurately measured volume of this stock solution,equivalent to about 40mg of mesalamine,to a 100-mLvolumetric flask,add a volume of 2Nhydrochloric acid,equal to the added stock solution volume,dilute with Mobile phaseto volume,and mix.Pass this solution through a suitable filter having a 0.5-µm or finer porosity.
Procedure— Proceed as directed in the Assay.Calculate the quantity,in g,of C7H7NO3in the container of Rectal Suspension taken by the formula:
20(C/V)(rU/rS),
in which Vis the volume,in mL,of stock solution taken to prepare the Test solution;and the other terms are as defined therein.
pHá791ñ: between 3.5and 5.5,when diluted 1to 10with water.
Related compounds—
Mobile phase,Standard solution,and Chromatographic system— Proceed as directed in Test 1for Related compoundsunder Mesalamine.
Test solution— Transfer an accurately measured volume of Rectal Suspension,previously well shaken,equivalent to 100mg of mesalamine,to a beaker,add water to give a volume of about 80mL,adjust with phosphoric acid to a pHof 2.0,sonicate briefly to dissolve,transfer to a 100-mLvolumetric flask,dilute with water to volume,and mix.
Procedure— Proceed as directed in the test for Related compoundsunder Mesalamine.Calculate the percentage of each impurity in the Rectal Suspension taken by the formula:
0.1CM(ri/rSM),
in which the terms are as defined therein.Not more than 0.2%of any individual impurity is found;and not more than 1.0%of total impurities is found.
Content of sodium benzoate (if present)—
Mobile phase— Transfer 390mg of ammonium acetate to a 1000-mLvolumetric flask,add 100mLof water,and dissolve by swirling.Add 6mLof glacial acetic acid and 300mLof methanol,dilute with water to volume,and mix.Pass this solution through a filter having a 0.5-µm or finer porosity.Make adjustments if necessary (see System Suitabilityunder Chromatography á621ñ).
Standard solution— Transfer about 100mg of sodium benzoate,accurately weighed,to a 100-mLvolumetric flask,dissolve in and dilute with water to volume,and mix.Transfer 5.0mLof this solution to a second 100-mLvolumetric flask,add 40mLof methanol,dilute with water to volume,and mix.Pass this solution through a filter having a 0.5-µm or finer porosity.
Test solution— Transfer about 5g of well-shaken Rectal Suspension,accurately weighed,to a 100-mLvolumetric flask,add 40mLof methanol,dilute with water to volume,and mix.Pass this solution through a filter having a 0.5-µm or finer porosity.
Chromatographic system— The liquid chromatograph is equipped with a 254-nm detector and a 4.6-mm ×25-cm column that contains packing L7.The flow rate is about 1.5mLper minute.Inject the Standard solutioninto the chromatograph,and record the peak responses as directed forProcedure:the tailing factor is not more than 2.5;and the relative standard deviation for replicate injections is not more than 2.0%.
Procedure— Separately inject equal volumes (about 15µL)of the Standard solutionand the Test solutioninto the chromatograph,record the chromatograms,and measure the responses for the major peaks.Calculate the percentage (w/w)of sodium benzoate in the Rectal Suspension taken by the formula:
10(C/W)(rU/rS),
in which Cis the concentration,in mg per mL,of sodium benzoate in the Standard solution;Wis the weight,in g,of the Rectal Suspension taken;and rUand rSare the responses obtained from the Test solutionand the Standard solution,respectively:it contains between 0.05%and 0.125%of sodium benzoate.
Assay—
Buffer solution,Mobile phase,Resolution solution,Standard preparation,andChromatographic system— Proceed as directed in the Assayunder Mesalamine.
Assay preparation— Transfer an accurately measured,well-shaken quantity of Rectal Suspension,equivalent to about 100mg of mesalamine,to a 100-mLvolumetric flask,add 55mLof Mobile phase,and dissolve by shaking for about 10minutes.Dilute with Mobile phaseto volume,and mix.Transfer 10.0mLof this solution to a 25-mLvolumetric flask,dilute with Mobile phaseto volume,and mix.Pass this solution through a suitable filter having a 0.5-µm or finer porosity,and use the filtrate as the Assay preparation.
Procedure— Proceed as directed in the Assayunder Mesalamine.Calculate the quantity,in mg,of mesalamine (C7H7NO3)in the portion of Rectal Suspension taken by the formula:
250C(rU/rS),
in which the terms are as defined therein.
Auxiliary Information— Staff Liaison:Daniel K.Bempong,Ph.D.,Scientist
Expert Committee:(PA2)Pharmaceutical Analysis 2
USP28–NF23Page 1221
Pharmacopeial Forum:Volume No.27(6)Page 3315
Phone Number:1-301-816-8143