Packaging and storage
Preserve in tight, light-resistant containers. Store up to 40
as permitted by the manufacturer.
Identification
A:
Infrared Absorption 197K: dried at 145
for 1 hour.
B:
To 1 mg in a porcelain crucible or small dish add 0.5 mL of sulfuric acid containing, in each mL, 1 drop of
formaldehyde TS: an intense purple color is produced at once, and quickly changes to deep blue-violet
(distinction from codeine, which gives at once an intense violet-blue color, and from hydromorphone, which gives at first a yellow to brown color, changing to pink and then to purplish red).
C:
To a solution of 5 mg in 5 mL of sulfuric acid in a test tube add 1 drop of
ferric chloride TS, mix, and heat in boiling water for 2 minutes: a blue color is produced, and when 1 drop of nitric acid is added, it changes to dark red-brown
(codeine and ethylmorphine give the same color reactions, but hydromorphone and papaverine do not produce this color change).
D:
A solution (1 in 50) responds to the tests for
Sulfate 191.
Acidity
Dissolve 500 mg in 15 mL of water, add 1 drop of
methyl red TS, and titrate with 0.020 N sodium hydroxide: not more than 0.50 mL is required to produce a yellow color.
Limit of foreign alkaloids
Dissolve 1.00 g in 10 mL of 1 N sodium hydroxide in a separator, and shake the solution with three successive portions of 15, 10, and 10 mL of chloroform, passing the chloroform solutions through a small filter previously moistened with chloroform. Shake the combined chloroform solutions with 5 mL of water, separate the chloroform layer, and carefully evaporate on a steam bath to dryness. To the residue add 10.0 mL of 0.020 N sulfuric acid, and heat gently until dissolved. Cool, add 2 drops of
methyl red TS, and titrate the excess acid with 0.020 N sodium hydroxide: not less than 7.5 mL is required (1.5%).
Assay
Mobile phase
Dissolve 0.73 g of sodium 1-heptanesulfonate in 720 mL of water, add 280 mL of methanol and 10 mL of glacial acetic acid, mix, filter, and degas. Make adjustments if necessary (see
System Suitability under
Chromatography 621).
Standard preparation
Dissolve an accurately weighed quantity of
USP Morphine Sulfate RS in
Mobile phase, and dilute quantitatively, and stepwise if necessary, with
Mobile phase to obtain a solution having a known concentration of about 0.24 mg per mL. Prepare a fresh solution daily.
System suitability preparation
Dissolve suitable quantities of
USP Morphine Sulfate RS and phenol in
Mobile phase to obtain a solution containing about 0.24 and 0.15 mg per mL, respectively.
Assay preparation
Transfer about 24 mg of Morphine Sulfate, accurately weighed, to a 100-mL volumetric flask, dissolve in and dilute with Mobile phase to volume, and mix.
Chromatographic system (see Chromatography 621)
The liquid chromatograph is equipped with a 284-nm detector and a 3.9-mm × 30-cm column that contains packing L1. The flow rate is about 1.5 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 0.7 for phenol and 1.0 for morphine sulfate; the resolution,
R, between phenol and morphine sulfate is not less than 2.0; the tailing factor for the morphine sulfate peak is not more than 2.0; and the relative standard deviation for replicate injections of the
Standard preparation is not more than 2.0%.
Procedure
Separately inject equal volumes (about 25 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 (C
17H
19NO
3)
2·H
2SO
4 in the portion of Morphine Sulfate taken by the formula:
100C(rU / rS),
in which
C is the concentration, in mg per mL, of anhydrous morphine sulfate in the
Standard preparation, as determined from the concentration of
USP Morphine Sulfate RS corrected for moisture content by a titrimetric water determination; and
rU and
rS are the peak responses obtained from the
Assay preparation and the
Standard preparation, respectively.