A: Transfer a quantity of Oral Solution, equivalent to about 15 mg of oxycodone, to a separator, add 10 mL of 0.01 N hydrochloric acid, and extract with four 40-mL portions of chloroform, collecting the chloroform extracts in a second separator. Wash the combined chloroform extracts with 5 mL of 0.01 N hydrochloric acid, and discard the chloroform layer. Combine the acidic wash with the aqueous solution remaining in the first separator, and adjust with 6 N ammonium hydroxide to a pH of 9.5 ± 0.5. Extract with one 50-mL and two 20-mL portions of chloroform, and filter the chloroform extracts through chloroform-washed cotton, collecting the filtrate in a 100-mL volumetric flask. Dilute with water-saturated chloroform to volume, and mix (test solution). Similarly prepare a Standard solution using about 12 mg of USP Oxycodone RS and 25 mL of 0.01 N hydrochloric acid, and proceed as directed above beginning with “extract with four 40-mL portions of chloroform.” The UV absorption spectrum of the test solution exhibits maxima and minima at the same wavelengths as that of the Standard solution, concomitantly measured.

B: Separately evaporate 5 mL of the test solution and 5 mL of the Standard solution obtained in Identification test A just to dryness. Dissolve each residue in 1.0 mL of chloroform. Apply separate 20-µL portions of the solution from the test solution and the solution from the Standard solution to a suitable thin-layer chromatographic plate (see Chromatography 621) coated with a 0.25-mm layer of chromatographic silica gel mixture. Allow the spots to dry, and develop the chromatogram in solvent system consisting of a mixture of acetone, toluene, ether, and ammonium hydroxide (6:4:1:0.3) until the solvent front has moved about three-fourths of the length of the plate. Remove the plate from the chamber, mark the solvent front, allow the solvent to evaporate, and spray with iodoplatinate TS: the principal spot obtained from the solution from the test solution corresponds in color, size, and RF value to that obtained from the solution from the Standard solution, and no other spots are observed.

C: The retention time of the oxycodone peak in the chromatogram of the Assay preparation corresponds to that in the chromatogram of the Standard preparation obtained as directed in the Assay.

FOR ORAL SOLUTION PACKAGED IN SINGLE-UNIT CONTAINERS: meets the requirements.

FOR ORAL SOLUTION PACKAGED IN MULTIPLE-UNIT CONTAINERS: meets the requirements.

(Official January 1, 2007)

Mobile phase, Standard preparation, and Chromatographic system— Proceed as directed in the Assay under Oxycodone Hydrochloride Tablets.

Assay preparation— Transfer an accurately measured volume of Oral Solution, equivalent to about 5 mg of oxycodone hydrochloride, to a 100-mL volumetric flask, dilute with Mobile phase to volume, and mix. Pass a portion of this mixture through a filter having a 0.5-µm or finer porosity, and use the clear filtrate as the Assay preparation.

Procedure— Proceed as directed for Procedure in the Assay under Oxycodone Hydrochloride Tablets. Calculate the quantity, in mg, of oxycodone hydrochloride (C18H21NO4·HCl) in each mL of the Oral Solution taken by the formula: in which V is the volume, in mL, of Oral Solution taken; and the other terms are as defined therein.