Identification—
Triturate 2 Tablets with 10 mL of water, and filter into 100 mL of acetone. Swirl the mixture, and allow to stand for 15 minutes to complete crystallization. Filter through a medium-porosity, sintered-glass filter, and wash the crystals with 25 mL of acetone. Apply vacuum to remove the solvent, then dry at 105
for 30 minutes, and cool: the residue so obtained responds to the
Identification test under
Aminocaproic Acid.
Dissolution 
711
—
Medium:
water; 900 mL.
Apparatus 1:
100 rpm.
Time:
45 minutes.
pH 9.5 Borate buffer—
Dissolve 6.185 g of boric acid and 7.930 g of potassium chloride in about 1000 mL of water, add 60 mL of 1.0 N sodium hydroxide, and mix. Dilute with water to 2000 mL, mix, and add 1.0 N sodium hydroxide, if necessary, to adjust to a pH of 9.5 ± 0.1.
Standard preparation—
Dissolve an accurately weighed quantity of
USP Aminocaproic Acid RS in water, and quantitatively dilute with water to obtain a solution having a known concentration of about 0.5 mg per mL.
Procedure—
Into three separate 50-mL volumetric flasks pipet (a) 1 mL of a filtered portion of the solution under test, (b) 1 mL of the
Standard preparation, and (c) 1 mL of water to provide a blank. Add 20.0 mL of
pH 9.5 Borate buffer and 3.0 mL of freshly prepared
-naphthoquinone-4-sodium sulfonate solution (1 in 500) to each, swirl to mix, and place the 3 flasks in a water bath maintained at a temperature of 65 ± 5
for 45 minutes. Cool, dilute each with water to volume, and mix. Determine the amount of C
6H
13NO
2 dissolved from absorbances, at the wavelength of maximum absorbance at about 460 nm, obtained from the test solution in comparison with those obtained from the Standard solution, using the blank to set the instrument.
Tolerances—
Not less than 75% (Q) of the labeled amount of C6H13NO2 is dissolved in 45 minutes.
