A: Triturate a quantity of Tablets, equivalent to about 5 mg of atropine sulfate, with 10 mL of water for a few minutes, and filter into a small separator. Render the solution alkaline with 6 N ammonium hydroxide, and extract with 50 mL of chloroform. Filter the chloroform layer, and evaporate to dryness. The residue so obtained meets the requirements under Identification—Organic Nitrogenous Bases 181.

B: A filtered solution of Tablets responds to the tests for Sulfate 191.

(Official January 1, 2007)

pH 9.0 Buffer, Internal standard solution, Standard preparation, and Chromatographic system— Proceed as directed in the Assay under Atropine Sulfate Ophthalmic Solution.

Assay preparation— Weigh and finely powder not fewer than 20 Tablets. Transfer an accurately weighed portion of the powder, equivalent to about 1 mg of atropine sulfate, to a separator, and proceed as directed for the Assay preparation in the Assay under Atropine Sulfate Ophthalmic Solution, beginning with “Add 2.0 mL of Internal standard solution.”

Procedure— Proceed as directed in the Assay under Atropine Sulfate Ophthalmic Solution. Calculate the quantity, in mg, of atropine sulfate [(C17H23NO3)2·H2SO4·H2O] in the portion of Tablets taken by the formula: in which 694.85 and 676.83 are the molecular weights of atropine sulfate monohydrate and anhydrous atropine sulfate, respectively; W is the weight, in mg, of USP Atropine Sulfate RS in the Standard preparation; and RU and RS are as defined therein.