» Octyldodecanol contains not less than 90.0 percent of 2-octyldodecanol, the remainder consisting chiefly of related alcohols.
Packaging and storage— Preserve in tight containers.
Identification— The retention time of the major peak in the chromatogram of the Assay preparation corresponds to that of the major peak in the chromatogram of the System suitability solution, as obtained in the Assay.
Acid value 401: not more than 0.5.
Iodine value 401: not more than 8.
Hydroxyl value 401: between 175 and 190.
Saponification value 401: not more than 5.
System suitability solution— Dissolve accurately weighed quantities of USP Octyldodecanol RS and USP Stearyl Alcohol RS in alcohol to obtain a solution having known concentrations of about 9 mg per mL and 1 mg per mL, respectively.
Assay preparation— Dissolve 90 mg of Octyldodecanol in 10.0 mL of alcohol, and mix.
Chromatographic system (see Chromatography 621)—The gas chromatograph is equipped with a flame-ionization detector and a 2-mm × 2-m column packed with 3% liquid phase G2 on support S1A. The carrier gas is nitrogen. The column temperature is programmed as follows. Initially it is equilibrated at about 80, then increased at a rate of 6 per minute to 300. The detector and the injection port temperatures are both maintained at about 280. Chromatograph the System suitability solution, and record the peak responses as directed for Procedure: the resolution, R, between octyldodecanol and stearyl alcohol is not less than 4.0; and the relative standard deviation for replicate injections is not more than 1.5%.
Procedure— Inject about 2 µL of the Assay preparation into the chromatograph, record the chromatogram, and measure the areas for the major peaks. Calculate the percentage of C20H42O in the portion of Octyldodecanol taken by the formula:
100(rU / rs)
in which rU is the peak area for octyldodecanol obtained from the Assay preparation; and rs is the sum of the areas of all the peaks except the solvent peak.
Auxiliary Information— Please check for your question in the FAQs before contacting USP.
Topic/Question Contact Expert Committee
Monograph Robert H. Lafaver, B.A.
(EM105) Excipient Monographs 1
Reference Standards Lili Wang, Technical Services Scientist
USP32–NF27 Page 1289
Chromatographic Column—
Chromatographic columns text is not derived from, and not part of, USP 32 or NF 27.