Test 1: If the product complies with this test,the labeling indicates that it meets USPDissolution Test 1.

Medium: 0.25MpH7.4phosphate buffer,prepared by mixing 5.175g of monobasic sodium phosphate and 30.17g of anhydrous dibasic sodium phosphate with water to obtain 1000mLof solution,and adjusting by the dropwise addition of 50%sodium hydroxide solution to a pHof 7.40±0.05;900mL.

Apparatus 2: 50rpm.

Time: 60minutes.

Procedure— Determine the amount of C14H10O5dissolved from UVabsorbances at the wavelength of maximum absorbance at about 308nm of filtered portions of the solution under test,suitably diluted with the Dissolution Medium,in comparison with a Standard solution having a known concentration of USP Salsalate RSin the same medium.

Tolerances— Not less than 70%(Q)of the labeled amount of C14H10O5is dissolved in 60minutes.

Test 2: If the product complies with this test,the labeling indicates that it meets USPDissolution Test 2.

Medium: 0.05M,pH7.5phosphate buffer;prepared by mixing 40.83g of monobasic potassium phosphate and 120mLof 2Nsodium hydroxide with water to obtain 6liters of solution,and adjusting by the dropwise addition of 2Nsodium hydroxide or phosphoric acid to a pHof 7.50±0.05;900mL.

Apparatus 2: 100rpm.

Time and Procedure— Proceed as directed for Test 1.

Tolerances— Not less than 70%(Q)of the labeled amount of C14H10O5is dissolved in 60minutes.

Mobile phase,Diluent,Resolution solution,and Chromatographic system— Proceed as directed in the Assay.

Standard preparation— Dissolve an accurately weighed quantity of USP Salicylic Acid RSin Diluentto obtain a stock solution having a known concentration of about 0.5mg per mL.Transfer 3.0mLof this solution to a 50-mLvolumetric flask,dilute with Diluentto volume,and mix.This solution contains about 0.03mg per mL.

Test preparation— Use the Assay stock solutionprepared as directed in the Assay.

Procedure— Proceed as directed for Procedurein the Assay,except to inject equal volumes (about 10µL)of the Standard preparationand the Test preparation.Calculate the percentage of salicylic acid (C7H6O3)in the portion of Tablets taken by the formula: in which Cis the concentration,in mg per mL,of USP Salicylic Acid RSin the Standard preparation,OTis the quantity,in mg,of salsalate in the portion of Tablets taken based on the labeled amount,and rUand rSare the salicylic acid peak responses obtained from the Test preparationand the Standard preparation,respectively:not more than 3.0%is found.

Mobile phase,Diluent,Salsalate standard preparation,Resolution solution,and Chromatographic system— Proceed as directed in the Assayunder Salsalate.

Assay preparation— Weigh and finely powder not less than 20Tablets.Transfer an accurately weighed portion of the powder,equivalent to about 100mg of salsalate,to a 100-mLvolumetric flask,dilute with Diluentto volume,and mix.Sonicate for about 10minutes,and mix.Filter a portion of this solution through a suitable filter of 0.5µm or finer porosity.Use the clear filtrate as the Assay stock solution.Transfer 2.0mLof the Assay stock solutionto a 100-mLvolumetric flask,dilute with Diluentto volume,and mix (Assay preparation).

Procedure— Proceed as directed for Procedurein the Assayunder Salsalate.Calculate the quantity,in mg,of C14H10O5in the portion of Tablets taken by the formula: in which Cis the concentration,in mg per mL,of USP Salsalate RSin the Salsalate standard preparation,and rUand rSare the responses of the salsalate peaks obtained from the Assay preparationand the Salsalate standard preparation,respectively.