Packaging and storage—
Preserve in tight, single-dose or multiple-dose
Containers for Injections, as described under
Injections 
1
. Store at controlled room temperature.
Identification—
Transfer 10 mL of the Injection to a separator, add
sodium hydroxide TS until alkaline to litmus, and extract with 25 mL of chloroform. Transfer a few drops of the chloroform extract to a KRS-5 plate, and allow to dry. Record the IR absorption spectrum by the attenuated total reflectance technique (see
Spectrophotometry and Light-Scattering 851). The spectrum thus obtained exhibits maxima only at the same wavelengths as that of a similar preparation of
USP Aminopentamide Sulfate RS, concomitantly measured.
Assay—
Mobile phase—
Transfer 14.4 g of sodium lauryl sulfate to a 500-mL volumetric flask, add 100 mL of glacial acetic acid, dilute with water to volume, mix, and pass through a filter having a 0.5-µm or finer porosity. Transfer 50 mL of this solution to a 1000-mL volumetric flask, add 350 mL of methanol and 350 mL of acetonitrile, dilute with water to volume, and mix. Filter and degas before use. Make adjustments if necessary (see
System Suitability under
Chromatography 621).
Standard preparation—
Quantitatively dissolve an accurately weighed quantity of
USP Aminopentamide Sulfate RS in water to obtain a solution having a known concentration equivalent to the labeled concentration of aminopentamide sulfate in the Injection.
Assay preparation—
Use the undiluted Injection.
Chromatographic system (see Chromatography 621)—
The liquid chromatograph is equipped with a 254-nm detector and a 3.9-mm × 30-cm column that contains packing L1 and is maintained at a constant temperature of about 40
. The flow rate is about 1 mL per minute. Chromatograph the
Standard preparation, and record the peak responses as directed for
Procedure: the tailing factor is not more than 2.5; and the relative standard deviation for replicate injections is not more than 2%.
Procedure—
Separately inject equal volumes (about 20 µL) of the
Standard preparation and the
Assay preparation into the chromatograph, record the chromatograms, and measure the areas for the major peaks. Calculate the quantity, in mg, of aminopentamide sulfate (C
19H
24N
2O·H
2SO
4) in each mL of the Injection taken by the formula:
C(rU / rS),
in which
C is the concentration, in mg per mL, of
USP Aminopentamide Sulfate RS in the
Standard preparation; and
rU and
rS are the aminopentamide peak responses obtained from the
Assay preparation and the
Standard preparation, respectively.
between 2.5 and 4.5.