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C14H22N2O 234.34

Acetamide, 2-(diethylamino)-N-(2,6-dimethylphenyl)-.
2-(Diethylamino)-2¢,6¢-acetoxylidide [137-58-6].
» Lidocaine contains not less than 97.5 percent and not more than 102.5 percent of C14H22N2O.
Packaging and storage— Preserve in well-closed containers.
A: Infrared Absorption 197K: previously dried in vacuum over silica gel for 24 hours.
B: To about 100 mg dissolved in 1 mL of alcohol add 10 drops of cobaltous chloride TS, and shake the solution for about 2 minutes: a bright green color develops, and a fine precipitate is formed.
Melting range 741: between 66 and 69.
Residue on ignition 281: not more than 0.1%.
Chloride 221 Dissolve 1.0 g in a mixture of 3 mL of 2 N nitric acid and 12 mL of water, and add 1 mL of silver nitrate TS: the turbidity does not exceed that produced by 50 µL of 0.020 N hydrochloric acid (0.0035%).
Sulfate— Dissolve about 200 mg in a mixture of 2 mL of 2 N nitric acid and 20 mL of water, and filter if necessary. To one-half of the filtrate add 1 mL of barium chloride TS: no more turbidity is produced than is present in the remaining portion of the filtrate to which nothing has been added.
Heavy metals, Method I 231 Dissolve 1.0 g in a mixture of 2 mL of 3 N hydrochloric acid and 10 mL of water, evaporate on a steam bath to dryness, and dissolve the residue in 25 mL of water: the limit is 0.002%.
Residual solvents 467: meets the requirements.
(Official January 1, 2007)
Mobile phase, Standard preparation, Resolution preparation, and Chromatographic system— Prepare as directed in the Assay under Lidocaine Hydrochloride.
Assay preparation— Dissolve about 85 mg of Lidocaine, accurately weighed, with warming if necessary, in 0.5 mL of 1 N hydrochloric acid in a 50-mL volumetric flask, dilute with Mobile phase to volume, and mix.
Procedure— Proceed as directed for Procedure in the Assay under Lidocaine Hydrochloride. Calculate the quantity, in mg, of C14H22N2O in the portion of Lidocaine taken by the formula:
50C(rU / rS),
in which C is the concentration, in mg per mL, of USP Lidocaine RS in the Standard preparation; and rU and rS are the lidocaine peak responses obtained from the Assay preparation and the Standard preparation, respectively.
Auxiliary Information— Staff Liaison : Daniel K. Bempong, Ph.D., Scientist
Expert Committee : (MDPS05) Monograph Development-Pulmonary and Steroids
USP29–NF24 Page 1251
Phone Number : 1-301-816-8143