A: Place 10mLof water in a small beaker,and deliver 3sprays from the Aerosol under the surface of the water,actuating the valve by pressing the tip against the bottom of the beaker.Filter,and to 5mLof the filtrate add 1drop of dilute hydrochloric acid (1in 120).Add 0.5mLof 0.1Niodine,allow to stand for 5minutes,and add 1mLof 0.1Nsodium thiosulfate:a red-brown color is produced.

B: Actuate the valve of the Aerosol by pressing the tip against a station of a white porcelain spot plate.Cover the spot with 2or 3drops of a mixture of 3volumes of pyridine and 1volume of acetic anhydride:an emerald-green color is produced.

PROCEDURE FOR DOSE UNIFORMITY—

Ferro-citrate solution andBuffer solution— Prepare as directed under Epinephrine Assay á391ñ.

Standard preparation— Prepare as directed under Delivered dose uniformity over the entire contents.

Assay preparation— [NOTE—Asuitable specimen beaker is one having a small indentation formed on its inside bottom surface having dimensions adequate to accept the aerosol valve stem during actuation,thereby preventing particle entrapment and side-of-stem leakage during the delivery of the specimen.]Place 20mLof chloroform in a suitable 100-mLbeaker.Prime the valve of Epinephrine Bitartrate Inhalation Aerosol by alternately shaking and firing it 10times through its oral inhalation actuator.Accurately weigh the Aerosol,shake it,and immediately deliver a single spray under the surface of the chloroform,actuating the valve by pressing the tip into the indentation in the bottom of the beaker.Raise the Aerosol above the surface of the chloroform,and shake it gently preparatory to delivering another spray similarly under the surface of the chloroform.Deliver a total of 3sprays in this manner.Rinse the valve stem and ferrule with about 2mLof chloroform,collecting the rinsing with the specimen in the beaker.Allow the Aerosol to dry,weigh it,and determine the total weight of the 3sprays.Transfer the solution to a centrifuge tube with the aid of two 3-mLportions of chloroform,and add 10.0mLof freshly prepared sodium bisulfite solution (1in 500).Insert the stopper,shake vigorously for 1minute,centrifuge for 5minutes,and use the clear supernatant as the Assay preparation.

Procedure— Transfer 5.0mLeach of the Standard preparationand the Assay preparationto separate test tubes.To each tube add 100µLof Ferro-citrate solutionand 1.0mLof Buffer solution,and mix.Concomitantly determine the absorbances of the solutions in 1-cm cells at the wavelength of maximum absorbance at about 530nm,with a suitable spectrophotometer,using water as the blank.Calculate the quantity,in mg,of C9H13NO3·C4H6O6in each mLof the Aerosol taken by the formula: in which Cis the concentration,in µg per mL,of USP Epinephrine Bitartrate RSin the Standard preparation,dis the density,in g per mL,of the Aerosol,determined as directed for din the Procedurein the Assayunder Isoproterenol Sulfate Inhalation Aerosol,Wis the weight,in g,of the specimen taken,and AUand ASare the absorbances of the solutions from the Assay preparationand the Standard preparation,respectively.