A: Infrared Absorption 197K.

B: Ultraviolet Absorption 197U—

Solution: 80 µg per mL.

Medium: 0.1 N hydrochloric acid.

Standard solution— Dissolve an accurately weighed quantity of USP Albuterol RS in methanol to obtain a solution having a known concentration of 0.10 mg per mL.

Test solution— Dissolve an accurately weighed quantity of Albuterol in methanol to obtain a solution having a concentration of 20 mg per mL.

Procedure— Apply 10-µL aliquots of the Test and the Standard solution to separate points on a thin-layer chromatographic plate (see Chromatography 621) coated with a 0.25-mm layer of chromatographic silica gel. Place the plate in a saturated chromatographic chamber, and develop the chromatogram in a solvent system consisting of a mixture of methyl isobutyl ketone, isopropyl alcohol, ethyl acetate, water, and ammonium hydroxide (50:45:35:18:3) until the solvent front has moved three-fourths of the length of the plate. Remove the plate from the developing chamber, air-dry, and expose it to iodine vapor: any spot, other than the principal spot, obtained from the Test solution is not greater in size and intensity than the spot produced by the Standard solution (0.5%), and the sum of the impurities is not greater than 2.0%.