» Piperazine contains not less than 98.0 percent and not more than 101.0 percent of C4H10N2, calculated on the anhydrous basis.
Packaging and storage Preserve in tight containers, protected from light.
Add the following:USP Reference standards 11
USP Piperazine RS.USP32
Color of solution Dissolve 10.0 g in water, and dilute with water to 50.0 mL: the solution has no more color than a standard solution prepared by adding 2.0 mL of ferric chloride CS to water and diluting with water to 50.0 mL, when compared in matched color-comparison tubes.
Change to read:Identification
B: In the test for Chromatographic purity, the principal spot in the chromatogram of Test solution 2, observed after spraying with the ninhydrin solutions, corresponds in RF value, color, and size to that in the chromatogram of Standard solution 1.USP32
Melting range 741: between 109 and 113.
Water, Method I 921: not more than 2.0%.
Delete the following:Primary amines and ammonia Disolve 200 mg in 10 mL of water, add 1 mL of acetone and 0.5 mL of freshly prepared sodium nitroferricyanide solution (1 in 10), mix, and allow to stand for 10 minutes, accurately timed. Determine the absorbance of this solution at 520 nm and at 600 nm, using a reagent blank as the reference solution. The ratio A600/A520 is not more than 0.5 (equivalent to about 0.7% of primary amines and ammonia).USP32
Add the following:Chromatographic purity
Solvent Prepare a mixture of 13.5 N ammonium hydroxide and dehydrated alcohol (3:2).
Standard solution 1 Prepare a solution of USP Piperazine RS in Solvent containing 10 mg per mL.
Standard solution 2 Prepare a solution of ethylenediamine in Solvent containing 0.25 mg per mL.
Standard solution 3 Prepare a solution of triethylenediamine in Solvent containing 0.25 mg per mL.
Resolution solution Prepare a solution in Solvent containing 0.25 mg of triethylenediamine and 10 mg of USP Piperazine RS per mL.
Test solution 1 Prepare a solution of Piperazine in Solvent containing 100 mg per mL.
Test solution 2 Mix 1 mL of Test solution 1 and 9 mL of Solvent.
Procedure Apply separate 5-µL portions of Standard solution 1, Standard solution 2, Standard solution 3, Resolution solution, Test solution 1, and Test solution 2 to a suitable thin-layer chromatographic plate (see Chromatography 621), coated with a 0.25-mm layer of chromatographic silica gel. Allow the spots to dry, and develop the chromatograms in a solvent system consisting of a freshly prepared mixture of acetone and 13.5 N ammonium hydroxide (80:20) until the solvent front has moved about three-fourths of the length of the plate. Remove the plate from the developing chamber, mark the solvent front, and dry the plate at 105. Spray the plate with a 0.3% (w/v) solution of ninhydrin in a mixture of butyl alcohol and glacial acetic acid (100:3). Spray the plate again with a 0.15% (w/v) solution of ninhydrin in dehydrated alcohol, dry the plate at 105 for 10 minutes, and examine the plate: any secondary spot in the chromatogram obtained from Test solution 1 is not more intense than the principal spot in the chromatogram obtained from Standard solution 2 (0.25%). Spray the plate with 0.1 N iodine TS, allow to stand for 10 minutes, and examine the plate: any spot corresponding to triethylenediamine in the chromatogram obtained from Test solution 1 is not more intense than the principal spot in the chromatogram obtained from Standard solution 3 (0.25%). In a valid test, the chromatogram obtained from the Resolution solution shows a spot due to triethylenediamine clearly separated from the principal spot. Disregard any spot at the origin of any chromatogram.USP32
Assay Weigh accurately about 150 mg of Piperazine, and dissolve in 75 mL of glacial acetic acid. Titrate potentiometrically with 0.1 N perchloric acid VS, using a silver-glass electrode system. As the endpoint is approached, warm the solution to 60 to 70, then complete the titration. Perform a blank determination, and make any necessary correction. Each mL of 0.1 N perchloric acid is equivalent to 4.307 mg of C4H10N2.
Auxiliary Information Please check for your question in the FAQs before contacting USP.
USP32NF27 Page 3313Pharmacopeial Forum: Volume No. 34(1) Page 105