Color and clarity
Transfer 2.0 mL of 0.100 N iodine VS to a 500-mL volumetric flask, dilute with water to volume, and mix.
Visually examine a portion of the Injection (Test solution) in a suitable clear glass test tube against a white background: it is not pinkish and it contains no precipitate. If any yellow color is observed in the Test solution, concomitantly determine the absorbances of the Test solution and the Standard solution in 1-cm cells with a suitable spectrophotometer set at 460 nm: the absorbance of the Test solution does not exceed that of the Standard solution.
To 1 L of 0.05 M monobasic sodium phosphate add about 519 mg of sodium 1-octanesulfonate and about 45 mg of edetate disodium, and mix. Adjust by the dropwise addition of phosphoric acid, if necessary, to a pH of 3.8. Mix 85 volumes of this solution with 15 volumes of methanol. Make adjustments if necessary (see System Suitability
under Chromatography 621
Dissolve an accurately weighed quantity of USP Epinephrine Bitartrate RS
in Mobile phase
, and dilute quantitatively, and stepwise if necessary, with Mobile phase
to obtain a solution having a known concentration of about 0.1 mg of epinephrine per mL.
Transfer an accurately measured volume of Injection, equivalent to about 1 mg of epinephrine, to a 10-mL volumetric flask, dilute with Mobile phase to volume, and mix.
System suitability preparation
Dissolve 10 mg of dopamine hydrochloride in 100 mL of the Standard preparation, and mix.
Chromatographic system (see Chromatography 621)
The liquid chromatograph is equipped with a 280-nm detector and a 4.6-mm × 15-cm column that contains packing L7. The flow rate is about 2 mL per minute. Chromatograph the Standard preparation
and the System suitability preparation
, and record the peak responses as directed for Procedure:
the relative retention times are about 1.0 for epinephrine and 2.0 for dopamine hydrochloride; the resolution, R,
between epinephrine and dopamine hydrochloride is not less than 3.5; and the relative standard deviation for replicate injections is not more than 2.0%.
Separately inject equal volumes (about 20 µL) of the Standard preparation
and the Assay preparation
into the chromatograph, record the chromatograms, and measure the responses for the major peaks. Calculate the quantity, in mg, of epinephrine (C9
) in each mL of the Injection taken by the formula:
(183.20/333.29)(10)(C/V)(rU / rS)
in which 183.20 and 333.29 are the molecular weights of epinephrine and epinephrine bitartrate, respectively; C
is the concentration, in mg per mL, of USP Epinephrine Bitartrate RS
in the Standard preparation; V
is the volume, in mL, of Injection taken; and rU
are the peak responses obtained from the Assay preparation
and the Standard preparation