Pentazocine and Naloxone Tablets
» Pentazocine and Naloxone Tablets contain amounts of Pentazocine Hydrochloride and Naloxone Hydrochloride equivalent to not less than 90.0 percent and not more than 110.0 percent of the labeled amounts of pentazocine (C19H27NO) and naloxone (C19H21NO4).
Packaging and storage Preserve in tight, light-resistant containers.
USP Reference standards 11
USP Naloxone RS.
USP Pentazocine RS.
Identification Crush 1 Tablet in 10 mL of a mixture of chloroform and methanol (1:1), and mix. Sonicate for about 2 minutes, and filter (Solution A). Evaporate 5 mL of Solution A to dryness on a steam bath under a stream of nitrogen. Dissolve the residue in 0.2 mL of the mixture of chloroform and methanol (1:1) (Solution B). Apply 10 µL of Solution A, 5 µL of Solution B, 10 µL of a Standard solution of USP Pentazocine RS in the 1:1 mixture of chloroform and methanol containing 5.0 mg per mL, and 5 µL of a Standard solution of USP Naloxone RS in the 1:1 mixture of chloroform and methanol containing 1.3 mg per mL to a suitable thin-layer chromatographic plate (see Chromatography 621) coated with a 0.25-mm layer of chromatographic silica gel mixture. Develop the chromatograms in a solvent system consisting of a mixture of 1-butanol, water, and glacial acetic acid (70:20:10) 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 under a current of warm air. Spray the plate with Folin-Ciocalteu Phenol TS followed by sodium hydroxide solution (1 in 10). Tests Solution A and Solution B exhibit spots having the same RF values and approximately the same size and shape as their respective Standard solutions.
Medium: water; 900 mL.
Apparatus 2: 50 rpm.
Time: 45 minutes.
Procedure Determine the amount of C19H27NO dissolved from UV absorption at the wavelength of maximum absorbance at about 279 nm (corrected for absorbance at 305 nm) on filtered portions of the solution under test, suitably diluted with Dissolution Medium, if necessary, in comparison with a Standard solution having a known concentration of USP Pentazocine RS prepared by dissolving the standard in a minimum volume of 0.1 N hydrochloric acid (about 4 mL per 100 mg) and diluting quantitatively and stepwise with water.
Tolerances Not less than 75% (Q) of the labeled amount of pentazocine (C19H27NO) is dissolved in 45 minutes.
Uniformity of dosage units 905: meet the requirements.
procedure for content uniformity for pentazocine and naloxone
Solvent mixture Use a mixture containing methanol, water, and phosphoric acid (500:500:1).
Mobile phase Prepare a filtered and degassed mixture by dissolving 675 mg of sodium 1-octanesulfonate and 426 mg of anhydrous dibasic sodium phosphate in 625 mL of water, and mix. Add 475 mL of methanol and 10 mL of phosphoric acid. Make adjustments if necessary (see System Suitability under Chromatography 621).
Strong anion-exchange resin Transfer about 30 g of strong anion-exchange resin to a 250-mL beaker. Wash the resin with two 200-mL portions of water, decanting the water after each wash. Wash with two 200-mL portions of dilute glacial acetic acid (1 in 20), decanting the first wash, and filter with the aid of suction.
Standard stock solution Transfer about 20 mg of USP Naloxone RS, accurately weighed, to a 100-mL volumetric flask. Dissolve in and dilute with Solvent mixture to volume, and mix.
Standard solution Transfer about 100 mg of USP Pentazocine RS, accurately weighed, to a 50-mL volumetric flask. Dissolve in about 30 mL of Solvent mixture. Add 5.0 mL of the Standard stock solution, dilute with Solvent mixture to volume, and mix.
Test solution Transfer 1 Tablet to a 25-mL glass-stoppered cylinder. Add 25.0 mL of Solvent mixture. Sonicate for 10 minutes, and shake intermittently for 15 minutes. Filter into a glass-stoppered conical flask. Add about 125 mg of Strong anion-exchange resin, and shake for 30 minutes.
Chromatographic system (see Chromatography 621) The liquid chromatograph is equipped with a 229-nm detector and a 4.6-mm × 25-cm column that contains packing L1. The flow rate is about 1.5 mL per minute. Chromatograph the Standard solution, and record the peak responses as directed for Procedure: the relative retention times are about 0.3 for naloxone and 1.0 for pentazocine; the resolution, R, between pentazocine and naloxone is not less than 6; and the relative standard deviation for replicate injections is not more than 2.0%.
Procedure Separately inject equal volumes (about 20 µL) of the Standard solution and the Test solution into the chromatograph, adjusting the operating parameters such that satisfactory chromatography and peak responses are obtained with the Standard solution. Record the chromatograms, and measure the areas for the major peaks. Calculate the quantities, in mg, of pentazocine (C19H27NO) and naloxone (C19H21NO4) in the Tablet taken by the same formula:
25C(rU / rS)in which C is the concentration, in mg per mL, of the appropriate USP Reference Standard in the Standard solution; and rU and rS are the peak responses for the corresponding analyte obtained from the Test solution and the Standard solution, respectively.
Assay for pentazocine and naloxone Proceed as directed for Procedure for content uniformity for pentazocine and naloxone, except to use the following Assay preparation in place of the Test solution, and to prepare the Standard preparation as directed for the Standard solution.
Assay preparation Weigh and finely powder not fewer than 20 Tablets. Transfer an accurately weighed portion of the powder, equivalent to about 100 mg of pentazocine, to a 100-mL volumetric flask, and add 50.0 mL of the Solvent mixture. Sonicate for 5 minutes, and shake intermittently for 15 minutes. Filter into a glass-stoppered conical flask. Add about 250 mg of Strong anion-exchange resin, and shake for 30 minutes.
Procedure Proceed as directed for Procedure under Uniformity of dosage units. Calculate the quantities, in mg, of pentazocine (C19H27NO) and naloxone (C19H21NO4), in the portion of the finely powdered Tablets taken by the same formula:
50C(rU / rS)in which C is the concentration, in mg per mL, of the appropriate USP Reference Standard in the Standard preparation; and rU and rS are the peak responses of the corresponding analyte obtained from the Assay preparation and the Standard preparation, respectively.
Auxiliary Information Please check for your question in the FAQs before contacting USP.Chromatographic Column
USP32NF27 Page 3246Pharmacopeial Forum: Volume No. 28(6) Page 1846
Chromatographic columns text is not derived from, and not part of, USP 32 or NF 27.