Packaging and storage— Preserve in well-closed containers.

Identification— Afiltered extract of Tablets responds to the tests for Sodium á191ñand for Chloride á191ñ.

Disintegration á701ñ: 30minutes.

Uniformity of dosage units á905ñ: meet the requirements.

Iodide or bromide— Digest 2.0g of powdered Tablets with 25mLof warm alcohol for 3hours,cool,and filter.Evaporate the filtrate to dryness,dissolve the residue in 5mLof water,filter if necessary,and add 1mLof chloroform.Cautiously introduce,dropwise,with constant agitation,5drops of dilute chlorine TS(1in 3):the chloroform does not acquire a violet,yellow,or orange color.

Barium— Digest 4.0g of powdered Tablets with 20mLof water,filter,and divide the solution into two equal portions.To one portion add 2mLof 2Nsulfuric acid and to the other add 2mLof water:the solutions are equally clear after standing for 2hours.

Calcium and magnesium— Digest 1g of powdered Tablets with 50mLof water,and filter.Add 4mLof 6Nammonium hydroxide to the filtrate,and divide the mixture into two equal portions.Treat one portion with 1mLof ammonium oxalate TSand the other portion with 1mLof dibasic sodium phosphate TS:neither mixture becomes turbid within 5minutes.

Assay— Dissolve a counted number of not less than 20Tablets in about 100mLof water,filter into a 500-mLvolumetric flask,and wash the original container and the filter with 100mLof water in divided portions,adding the washings to the original filtrate.Dilute with water to volume.Pipet a volume of the solution,equivalent to about 90mg of sodium chloride,to a conical flask,and add 10mLof glacial acetic acid,75mLof methanol,and 0.5mLof eosin Y TS.Titrate,with shaking,with 0.1Nsilver nitrate VSto a pink endpoint.Each mLof 0.1Nsilver nitrate is equivalent to 5.844mg of NaCl.

Expert Committee:(PA1)Pharmaceutical Analysis 1

USP28–NF23Page 1782

Phone Number:1-301-816-8379