U.S. PHARMACOPEIA

Search USP29  
Isopropyl Alcohol
Click to View Image
C3H8O 60.10

2-Propanol.
Isopropyl alcohol [67-63-0].
» Isopropyl Alcohol contains not less than 99.0 percent of C3H8O.
Packaging and storage— Preserve in tight containers, remote from heat.
Identification— The IR absorption spectrum of a thin film of it exhibits a strong broad band at 3.0 µm; a strong region of absorption between 3.35 and 3.5 µm, with its highest peak at about 3.36 µm, and others at about 3.41 and 3.47 µm; a strong region of absorption between 6.7 and 7.8 µm, the most prominent features being the peaks at about 6.80, 7.10, 7.25 (the highest), 7.50, and 7.65 µm; a strong region of absorption between 8.5 and 9.2 µm, peaking at about 8.6, 8.85, and 9.0 µm; and strong peaks at about 10.5 and 12.3 µm.
Specific gravity 841: between 0.783 and 0.787.
Refractive index 831: between 1.376 and 1.378 at 20.
Acidity— To 50 mL in a suitable flask add 100 mL of carbon dioxide-free water. Add 2 drops of phenolphthalein TS, and titrate with 0.020 N sodium hydroxide to a pink color that persists for 30 seconds: not more than 0.70 mL of 0.020 N sodium hydroxide is required for neutralization.
Limit of nonvolatile residue— Evaporate 50 mL in a tared porcelain dish on a steam bath to dryness, and heat at 105 for 1 hour: the weight of the residue does not exceed 2.5 mg (0.005%).
Residual solvents 467: meets the requirements.
(Official January 1, 2007)
Assay— Inject about 5 µL of Isopropyl Alcohol into a suitable gas chromatograph, equipped with a thermal conductivity detector. Under typical conditions, the gas chromatograph contains a 1.8-m × 6.4-mm (OD) stainless steel column packed with 10% liquid phase G20 on support S1A, the column is maintained at 55, and helium is used as the carrier gas at a flow rate of 45 mL per minute. Relative retention times of some of the possible components, when present, are: air at 0.09, diethyl ether at 0.14, diisopropyl ether at 0.17, acetone at 0.37, isopropyl alcohol at 1.00, 2-butanol at 1.64, n-propyl alcohol at 1.86, and water at 3.14. Calculate the percentage of C3H8O in the Isopropyl Alcohol by dividing the area under the isopropyl alcohol peak by the sum of the areas under all of the peaks observed, and multiplying by 100.
Auxiliary Information— Staff Liaison : Behnam Davani, Ph.D., MBA, Senior Scientist
Expert Committee : (MDAA05) Monograph Development-Antivirals and Antimicrobials
USP29–NF24 Page 1192
Pharmacopeial Forum : Volume No. 31(5) Page 1375
Phone Number : 1-301-816-8394