Dibucaine Hydrochloride
C20H29N3O2·HCl 379.92

4-Quinolinecarboxamide,2-butoxy-N-[2-(diethylamino)ethyl]-,monohydrochloride.
2-Butoxy-N-[2-(diethylamino)ethyl]cinchoninamide monohydrochloride [61-12-1].
»Dibucaine Hydrochloride contains not less than 97.0percent and not more than 100.5percent of C20H29N3O2·HCl,calculated on the dried basis.
Packaging and storage— Preserve in tight,light-resistant containers.
Identification—
A: Infrared Absorption á197Mñ.
Solution: 10µg per mL.
Medium: 1Nhydrochloric acid.
Absorptivities at 247nm,calculated on the dried basis,do not differ by more than 3.0%.
C: Asolution of it responds to the tests for Chloride á191ñwhen tested as specified for alkaloidal hydrochlorides.
Loss on drying á731ñ— Dry it at 80for 5hours:it loses not more than 2.0%of its weight.
Residue on ignition á281ñ: not more than 0.1%.
Chromatographic purity— Dissolve a suitable quantity of Dibucaine Hydrochloride,accurately weighed,in chloroform to obtain a Test solutionhaving a concentration of 40.0mg per mL.Dissolve a suitable quantity of USP Dibucaine Hydrochloride RS,accurately weighed,in chloroform to obtain a Standard solutionhaving a known concentration of about 40mg per mL.Dilute portions of this solution quantitatively and stepwise with chloroform to obtain three Comparison solutionshaving concentrations of 40,120,and 200µg per mL(0.1%,0.3%,and 0.5%)of the Standard solution,respectively.Apply separate 5-µLportions of the five solutions to the starting line of a suitable thin-layer chromatographic plate (see Chromatography á621ñ)coated with a 0.25-mm layer of chromatographic silica gel mixture.Develop the chromatogram in a solvent system consisting of a mixture of toluene,acetone,methanol,and ammonium hydroxide (50:30:5:1)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,and air-dry.Spray the plate heavily with a 1in 200solution of potassium dichromate in dilute sulfuric acid (1in 5).Place the plate in an oven at 140for 10minutes,and view under short-wavelength UVlight:the principal spot obtained from the Test solutioncorresponds in RFvalue,color,and intensity to that obtained from the Standard solution;the sum of the intensities of any secondary spots,if present in the chromatogram from the Test solution,corresponds to not more than 1.0%,and the intensity of any secondary spot does not exceed 0.5%of that of the principal spot on the chromatogram from the Standard solutionon the basis of comparison with the spots obtained from the Comparison solutions.
Assay—
Mobile phase,Solvent mixture,Standard preparation,and Chromatographic system— Proceed as directed in the Assayunder Dibucaine.
Assay preparation— Transfer about 100mg of Dibucaine Hydrochloride,accurately weighed,to a 100-mLvolumetric flask,add Solvent mixtureto volume,and mix.Filter through a suitable filter having a porosity of 0.5µm or finer.
Procedure— Proceed as directed for Procedurein the Assayunder Dibucaine.Calculate the quantity,in mg,of C20H29N3O2·HCl in the portion of Dibucaine Hydrochloride taken by the formula:
100C(rU/rS),
in which Cis the concentration,in mg per mL,of USP Dibucaine Hydrochloride RSin the Standard preparation,and rUand rSare the responses of the dibucaine peaks obtained from the Assay preparationand the Standard preparation,respectively.
Auxiliary Information— Staff Liaison:Karen A Russo,Ph.D.,Scientist
Expert Committee:(PA1)Pharmaceutical Analysis 1
USP28–NF23Page 623
Pharmacopeial Forum:Volume No.29(5)Page 1458
Phone Number:1-301-816-8379