Procainamide Injection

General Notices

Action and use

Class I antiarrhythmic.

Definition

Procainamide Injection is a sterile solution of Procainamide Hydrochloride in Water for Injections.

The injection complies with the requirements stated under Parenteral Preparations and with the following requirements.

Content of procainamide hydrochloride, C13H21N3O,HCl

95.0 to 105.0% of the stated amount.

Characteristics

A colourless or almost colourless solution.

Identification

A. Dilute a volume containing 0.25 g of Procainamide Hydrochloride to 25 mL with water, make alkaline with 5m sodium hydroxide and extract with two 10 mL quantities of chloroform. Filter the combined extracts through anhydrous sodium sulfate, evaporate the filtrate to dryness using a rotary evaporator and dissolve the residue in 5 mL of chloroform. The infrared absorption spectrum of the resulting solution, Appendix II A, is concordant with the reference spectrum of procainamide (RS 288).
B. Dilute with water to produce a solution containing 0.0005% w/v of Procainamide Hydrochloride. The absorbance at 280 nm is about 0.30, Appendix II B.
C. Yields reaction A characteristic of chlorides, Appendix VI.

Tests

Acidity

pH, 4.0 to 5.5, Appendix V L.

Related substances

Carry out the method for thin-layer chromatography, Appendix III A, using the following solutions in methanol.

(1) Dilute a volume of the injection containing 0.10 g of Procainamide Hydrochloride to 5 mL.
(2) Dilute 1 volume of solution (1) to 100 volumes.
chromatographic conditions
(a) Use as the coating silica gel G.
(b) Use the mobile phase as described below.
(c) Apply 10 µL of a 20% v/v solution of 13.5m ammonia in methanol to each point of application and 10 µL of each solution.
(d) Develop the plate to 15 cm.
(e) After removal of the plate, dry in air, spray with alcoholic dimethylaminobenzaldehyde solution.
mobile phase

0.7 volumes of 13.5m ammonia, 30 volumes of methanol and 70 volumes of chloroform.

limits

Any secondary spot in the chromatogram obtained with solution (1) is not more intense than the spot in the chromatogram obtained with solution (2) (1%).

Assay

To a volume containing 0.5 g of Procainamide Hydrochloride add 45 mL of 6m hydrochloric acid and boil for 1 minute. Cool and titrate with 0.1m sodium nitrite VS, using 1 mL of ferrocyphen solution as indicator, until a violet colour is produced that is stable for not less than 3 minutes. Repeat the operation without the injection. The difference between the titrations represents the amount of sodium nitrite required. Each mL of 0.1m sodium nitrite VS is equivalent to 27.18 mg of C13H21N3O,HCl.