Packaging and storage
Preserve in single-dose or in multiple-dose containers,preferably of Type Iglass.
Identification,Infrared Absorption á197Kñ
Obtain the test specimen as follows.Filter a volume of Injectable Suspension,equivalent to about 100mg of methylprednisolone acetate,through paper.Wash the residue with several 5-mLportions of water,and dry at 105

for 3hours.
Particle size
Transfer 1drop to a microscope slide,and spread evenly,diluting with water,if necessary,to decrease the density of the field.Examine the slide under a microscope,equipped with a calibrated ocular micrometer,using about 400×magnification.Scan the entire slide,and note the size of the individual particles:not less than 99%of the particles are less than 20µm in length when measured along the longest axis,and not less than 75%of the particles are less than 10µm.
Assay
Assay preparation
Swirl the Injectable Suspension to ensure uniformity prior to analysis.Transfer an accurately measured volume of Injectable Suspension,equivalent to about 40mg of methylprednisolone acetate,to a 25-mLvolumetric flask,add 10.0mLof Internal standard solution,dilute with chloroform to volume,and shake for about 15minutes or until the aqueous layer is clear.Transfer 4.0mLof the chloroform layer to a suitable vial,add 30mLof chloroform and a small quantity (about 400mg)of anhydrous sodium sulfate,shake for 5minutes,and use the clear solution.
Procedure
Proceed as directed for
Procedurein the
Assayunder
Methylprednisolone Acetate.Calculate the quantity,in mg,of methylprednisolone acetate (C
24H
32O
6)in each mLof the Injectable Suspension taken by the formula:
(200C/V)(RU/RS),
in which
Vis the volume,in mL,of Injectable Suspension taken,and the other terms are as defined therein.