A: Dissolve the contents of 5 Capsules in 20 mL of water, and filter: the filtrate responds to the tests for Potassium 191.

B: Add a few drops of methylene blue solution (1 in 1000) to the filtrate obtained in Identification test A: a violet-colored precipitate is obtained.

Mobile phase, Standard preparation, and Chromatographic system— Proceed as directed in the Assay under Potassium Perchlorate.

Assay preparation— Mix the contents of not less than 10 Capsules, and transfer an accurately weighed portion of the mixed powder, equivalent to about 200 mg of potassium perchlorate, to a 200-mL volumetric flask, dilute with water to volume, and mix. Pass through a filter having 0.22-µm pore size, transfer 10.0 mL of the clear filtrate to a 100-mL volumetric flask, dilute with water to volume, and mix.

Procedure— Proceed as directed in the Assay under Potassium Perchlorate. Calculate the quantity, in mg, of potassium perchlorate (KClO4) in the portion of Capsules taken by the formula: in which the terms are as defined therein.