Identification—
Prepare a solution of Capsule contents in methanol containing 20 mg per mL, and filter. The clear filtrate so obtained meets the requirements of the
Thin-Layer Chromatographic Identification Test 
201
, the solvent mixture consisting of methylene chloride, methyl ethyl ketone, and glacial acetic acid (50:48:2).
Dissolution 711—
Apparatus 2:
50 rpm.
Time:
45 minutes.
Procedure—
Determine the amount of meclofenamic acid (C
14H
11Cl
2NO
2) dissolved from UV absorbances at the wavelength of maximum absorbance at about 279 nm of filtered portions of the solution under test, suitably diluted with
Medium, if necessary, in comparison with a Standard solution having a known concentration of
USP Meclofenamate Sodium RS in the same
Medium.
Tolerances—
Not less than 75% (Q) of the labeled amount of C14H11Cl2NO2 is dissolved in 45 minutes.
Assay—
Remove, as completely as possible, the contents of not fewer than 20 Capsules, and weigh accurately. Mix the combined contents, and transfer an accurately weighed quantity of the powder, equivalent to about 50 mg of meclofenamic acid, to a 200-mL volumetric flask. Add 0.01 N hydrochloric acid in methanol to volume, and mix. Filter, discarding the first 20 mL of the filtrate. Transfer 10.0 mL of the filtrate to a 100-mL volumetric flask, add 0.01 N hydrochloric acid in methanol to volume, and mix. Dissolve an accurately weighed quantity of
USP Meclofenamate Sodium RS in 0.01 N hydrochloric acid in methanol to obtain a solution having a known concentration of about 27 µg per mL. Concomitantly determine the absorbances of both solutions in 1-cm cells at the wavelength of maximum absorbance at about 336 nm, with a suitable spectrophotometer, using 0.01 N hydrochloric acid in methanol as the blank. Calculate the quantity, in mg, of meclfenamate acid (C
14H
11Cl
2NO
2) in the portion of Capsule contents taken by the formula:
2C(296.15 / 318.13)(AU / AS),
in which
C is the concentration, in µg per mL, of
USP Meclofenamate Sodium RS in the Standard solution; 296.15 and 318.13 are the molecular weights of meclofenamic acid and meclofenamate sodium, respectively; and
AU and
AS are the absorbances of the solution from the Capsule contents and the Standard solution, respectively.
