Packaging and storage—
Preserve in single-dose or multiple-dose containers, preferably of Type I glass, protected from light. To avoid precipitation, store at a temperature of not below 15
, but avoid excessive heat.
Identification—
A:
Dilute about 5 mL with 20 mL of water, and add 1.0 mL of 2 N sodium hydroxide and 2 drops of
potassium permanganate TS: a green color is produced.
B:
The retention time of the major peak in the chromatogram of the
Assay preparation corresponds to that of the
Standard preparation obtained as directed in the
Assay.
C:
Transfer a portion of Injection, equivalent to about 100 mg of dyphylline, to a 200-mL volumetric flask, dilute with water to volume, and mix. Transfer 2 mL to a 100-mL volumetric flask, dilute with water to volume, and mix: the UV absorption spectrum of the solution exhibits maxima and minima at the same wavelengths as that of a solution of
USP Dyphylline RS containing 10 µg per mL, concomitantly measured.
Assay—
Mobile phase, Standard preparation, and Chromatographic system—
Prepare as directed in the
Assay under
Dyphylline Tablets.
Assay preparation—
Transfer an accurately measured volume of Injection, equivalent to about 100 mg of dyphylline, to a 500-mL volumetric flask, add water to volume, and mix.
Procedure—
Proceed as directed in the
Assay under
Dyphylline Tablets. Calculate the quantity, in mg, of C
10H
14N
4O
4 in each mL of the Injection taken by the formula:
(0.5C / V)(rU / rS),
in which
V is the volume, in mL, of Injection taken, and the other terms are as defined therein.
85
—
It contains not more than 0.7 USP Endotoxin Unit per mg of dyphylline.