A: The retention time of the major peak in the chromatogram of the Assay preparation corresponds to that in the chromatogram of the Standard preparation, as obtained in the Assay.

B: It meets the requirements of the tests for Chloride 191.

C: It meets the requirements of the tests for Sulfate 191 (only for Tablets labeled as containing glucosamine sodium sulfate or glucosamine potassium sulfate).

Medium: water; 900 mL.

Apparatus 2: 75 rpm.

Time: 60 minutes.

Phosphate buffer, Mobile phase, and Chromatographic system— Proceed as directed in the Assay under Glucosamine Hydrochloride.

Standard solution— Dissolve an accurately weighed quantity of USP Glucosamine Hydrochloride RS in water to obtain a solution having a known concentration of about 1.0 mg per mL. Dilute with a suitable quantity of water, if necessary.

Test solution— Use the solution under test.

Procedure— Separately inject equal volumes (about 10 µL) of the Standard solution and the Test solution into the chromatograph, record the chromatograms, and measure the areas for the glucosamine peaks. Calculate the amount, in mg, of C6H13NO5 dissolved by the formula: in which 179.17 and 215.63 are the molecular weights of glucosamine and glucosamine hydrochloride, respectively; C is the concentration, in mg per mL, of USP Glucosamine Hydrochloride RS in the Standard solution; and rU and rS are the peak responses obtained from the Test solution and the Standard solution, respectively.

Tolerances— Not less than 75% of the labeled amount of C6H13NO5 is dissolved in 60 minutes.

Phosphate buffer, Mobile phase, Standard preparation, and Chromatographic system— Proceed as directed in the Assay under Glucosamine Hydrochloride.

Assay preparation— Weigh and finely powder not fewer than 20 Tablets. Transfer an accurately weighed portion of the finely powdered material, equivalent to about 80 mg of glucosamine, to a 100-mL volumetric flask, add 60 mL of water, and sonicate for 10 minutes. Shake by mechanical means for 15 minutes. Dilute with water to volume, and mix. Pass a portion of this solution through a membrane filter having a 0.45-µm or finer porosity.

Procedure— Separately inject equal volumes (about 10 µL) of the Standard preparation and the Assay preparation into the chromatograph, record the chromatograms, and measure the responses for the major peaks. Calculate the quantity, in mg, of glucosamine (C6H13 NO5) in the portion of Tablets taken by the formula: in which 179.17 and 215.63 are the molecular weights of glucosamine and glucosamine hydrochloride, respectively; C is the concentration, in mg per mL, of USP Glucosamine Hydrochloride RS in the Standard preparation; and rU and rS are the peak responses obtained from the Assay preparation and the Standard preparation, respectively.