Chromatographic purity
Mobile phase and Chromatographic system
Prepare as directed in the Assay.
Test solution
Transfer about 100 mg of Cyclandelate, accurately weighed, to a 100-mL volumetric flask, dissolve in and dilute with Mobile phase to volume, and mix.
Standard solution
Pipet 3.0 mL of the Test solution into a 100-mL volumetric flask, dilute with Mobile phase to volume, and mix.
Procedure
Separately inject equal volumes (about 10 µL) of the Test solution and the Standard solution into the chromatograph, record the chromatograms, and measure the areas for all the peaks. Allow the chromatogram of the Test solution to run for a period of time that is about 3 times the retention time of cyclandelate. The total area of all the peaks from the Test solution, other than the peak obtained from cyclandelate, is not greater than the peak area of cyclandelate obtained from the Standard solution: not more than 3.0% of total impurities is found.
Assay
Mobile phase
Prepare a filtered and degassed mixture of acetonitrile and water (4:1). Make adjustments if necessary (see
System Suitability under
Chromatography 621).
Resolution solution
Dissolve accurately weighed quantities of
USP Cyclandelate RS and dicyclohexyl phthalate in
Mobile phase to obtain a solution having known concentrations of about 0.2 mg per mL and 0.08 mg per mL, respectively.
Standard preparation
Dissolve an accurately weighed quantity of
USP Cyclandelate RS in
Mobile phase to obtain a solution having a known concentration of about 1.0 mg per mL. Pipet 10.0 mL of this solution into a 50-mL volumetric flask, dilute with
Mobile phase to volume, and mix.
Assay preparation
Transfer about 100 mg of Cyclandelate, accurately weighed, to a 100-mL volumetric flask, dissolve in and dilute with Mobile phase to volume, and mix. Pipet 10.0 mL of this solution into a 50-mL volumetric flask, dilute with Mobile phase to volume, and mix.
Chromatographic system (see Chromatography 621)
The liquid chromatograph is equipped with a 228-nm detector and a 4.0-mm × 15-cm column that contains packing L1. The flow rate is about 1.0 mL per minute. Chromatograph the
Resolution solution, and record the peak responses as directed for
Procedure: the resolution,
R, between cyclandelate and dicyclohexyl phthalate is not less than 7. Chromatograph the
Standard preparation, and record the peak responses as directed for
Procedure: the relative standard deviation for replicate injections is not more than 2.0%.
Procedure
Separately inject equal volumes (about 10 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 C
17H
24O
3 in the portion of Cyclandelate taken by the formula:
500C(rU / rS),
in which
C is the concentration, in mg per mL, of
USP Cyclandelate RS in the
Standard preparation; and
rU and
rS are the peak responses obtained from the
Assay preparation and the
Standard preparation, respectively.