Dissolution 
2040
—
Medium:
0.1 N hydrochloric acid; 500 mL.
Apparatus 2:
75 rpm.
Time:
60 minutes.
NOTE—In each dissolution vessel, place a number of Capsules equivalent to about 20 mg of the labeled amounts of gingerols, gingerdiones, and shogaols.
Mobile phase—
Prepare as directed in the test for
Content of gingerols and gingerdiones under
Ginger.
Standard stock solution—
Use the
Standard preparation, prepared as directed in the test for
Content of gingerols and gingerdiones under
Ginger.
Standard solution—
Transfer 1.0 mL of the
Standard stock solution to a 10-mL volumetric flask, and dilute with
Medium to volume to obtain a solution having a known concentration of about 0.025 mg of
USP Capsaicin RS per mL.
Test solution—
Transfer an aliquot of solution from each dissolution vial to a suitable vial. Allow to stand for 5 minutes so the powder settles into the suspension, or centrifuge to obtain a clear supernatant. Pass through a membrane filter having a 0.45-µm or finer porosity.
Chromatographic system—
Proceed as directed in the test for
Content of gingerols and gingerdiones under
Ginger. To evaluate the system suitability requirements, use the
Standard preparation and the
System suitability solution, prepared as directed in the test for
Content of gingerols and gingerdiones under
Ginger.
Procedure—
Separately inject equal volumes (about 20 µL) of the
Standard solution and the
Test solution into the chromatograph, and allow the
Test solution to elute for not less than three times the retention time of capsaicin. Record the chromatograms, and measure all of the peak responses. Calculate the quantity, in mg, of 6-gingerol dissolved,
G, from each Capsule taken by the formula:
500(C/N)(rU / rS),
in which
C is the concentration, in mg per mL, of
USP Capsaicin RS in the
Standard solution; N is the number of Capsules in each vessel;
rU is the peak response for 6-gingerol obtained from the
Test solution; and
rS is the peak response for capsaicin obtained from the
Standard solution. Calculate the percentage of the relative amount of 6-gingerol dissolved by the formula:
100(G/G0),
in which
G0 is the content of 6-gingerol, in mg, in each Capsule, as determined in the test for
Content of gingerols, gingerdiones, and shogaols.
Tolerances—
Not less than 60% of the content of 6-gingerol (C17H26O4) is dissolved in 60 minutes.
Content of gingerols, gingerdiones, and shogaols—
Mobile phase, Standard preparation, System suitability solution, and Chromatographic system—
Proceed as directed in the test for
Content of gingerols and gingerdiones under
Ginger.
Test preparation—
Carefully open not fewer than 20 Capsules, and transfer about 1.0 g of the powder, accurately weighed, to a glass-stoppered conical flask. Add 50 mL of alcohol, insert a stopper into the flask, and macerate for 24 hours, shaking frequently during the first 8 hours, and then allowing to stand for 18 hours. Filter, and evaporate the solvent to dryness in a vacuum. Quantitatively transfer the contents with the aid of methanol to a 10-mL volumetric flask, add methanol to volume, and mix.
Procedure—
Proceed as directed in the test for
Content of gingerols and gingerdiones under
Ginger. Calculate the amounts, in mg, of gingerols, gingerdiones, and shogaols in the portion of the Capsules taken by the formula:
10C(rU / rS),
in which
C is the concentration, in mg per mL, of
USP Capsaicin RS in the
Standard preparation; rU is the sum of peak responses for gingerols, gingerdiones, and shogaols; and
rS is the peak response for capsaicin obtained from the
Standard preparation. Calculate the amount, in mg, of 6-gingerol in the portion of Capsules taken by the formula:
10C(rU / rS),
in which
rU is the peak response for 6-gingerol obtained from the
Test preparation; and the other terms are as defined above.
