A: Thin-Layer Chromatographic Identification Test 201—

Adsorbent: chromatographic silica gel mixture; 0.25 mm.

Developing solvent: mixture of butyl alcohol, water, dehydrated alcohol, and glacial acetic acid (6:2:1:1).

Test preparation: Bupivacaine Hydrochloride in Dextrose Injection.

Standard preparations A , B, and C—Separately prepare (A) a solution of USP Bupivacaine Hydrochloride RS in water, (B) a solution of USP Dextrose RS in water, and (C) a solution of USP Bupivacaine Hydrochloride RS in (B) to obtain solutions having concentrations corresponding to the labeled concentrations of bupivacaine hydrochloride and dextrose in the Injection.

Naphthalenediol reagent— Dissolve 20 mg of 1,3-naphthalenediol in 10 mL of dehydrated alcohol containing 0.2 mL of sulfuric acid.

Iodoplatinate reagent— Mix equal volumes of platinic chloride solution (3 in 1000) and potassium iodide solution (6 in 100).

Procedure— Separately apply 10 µL each of the Test preparation and Standard preparations A and C to a portion of the chromatographic plate, and separately apply 1 µL each of the Test preparation and Standard preparation B to the remaining portion of the plate. Dry the applications in a current of warm air, develop the chromatograms, remove the plate from the developing chamber, and mark the solvent front. Dry the plate in warm circulating air, and examine the plate under short-wavelength UV light: the RF value of the principal spot obtained from the Test preparation corresponds to the spots obtained from the adjacent chromatograms of Standard preparations A and C. Spray the plate with Naphthalenediol reagent, heat at 90 for 5 minutes, and examine the plate: the RF value of the principal blue-purple spot obtained from the Test preparation corresponds to that obtained in the adjacent chromatogram of Standard preparation B. Cool the plate, spray it with Iodoplatinate reagent, and examine the plate: bupivacaine appears as a blue-purple spot on a salmon-colored background, and the dextrose spots fade slightly: the RF value of the bupivacaine spot obtained from the Test preparation corresponds to those obtained from the adjacent chromatograms of Standard preparations A and C.

B: It responds to Identification test B under Bupivacaine Hydrochloride Injection.

(Official January 1, 2007)

pH 6.8 Phosphate buffer, Mobile phase, Internal standard solution, Standard preparation, Chromatographic system, and Procedure— Proceed as directed in the Assay under Bupivacaine Hydrochloride Injection.

Assay preparation— Transfer an accurately measured volume of Injection, equivalent to about 50 mg of bupivacaine hydrochloride, to a 100-mL volumetric flask, add 10.0 mL of Internal standard solution, dilute with methanol to volume, and mix.

(100/52.9)AR,