Action and use
Local anaesthetic.
DEFINITION
Prilocaine Injection is a sterile solution of Prilocaine Hydrochloride in Water for Injections.
The injection complies with the requirements stated under Parenteral Preparations and with the following requirements.
Content of prilocaine hydrochloride, C13H20N2O,HCl
95.0 to 105.0% of the stated amount.
CHARACTERISTICS
A colourless solution.
IDENTIFICATION
A. To a volume containing 0.1 g of Prilocaine Hydrochloride add 2M sodium hydroxide until the solution is about pH 11.
Add 20 mL of ethyl acetate, shake, allow the layers to separate, dry the organic layer over anhydrous calcium chloride at a pressure of 2 kPa, filter and evaporate the filtrate to dryness under reduced pressure. The infrared absorption spectrum of the oily residue, Appendix II A, is concordant with the reference spectrum of prilocaine (RS 284).
B. In the Assay, the principal peak in the chromatogram obtained with solution (3) has the same retention time as the peak due to prilocaine in the chromatogram obtained with solution (1).
TESTS
Acidity
pH, 5.0 to 7.0, Appendix V L.
Aromatic amines
To 1 mL of the injection, diluted if necessary to contain 0.05% w/v of Prilocaine Hydrochloride, add 1 mL of a 1% w/v solution of 4-dimethylaminobenzaldehyde in methanol and 2 mL of glacial acetic acid. Shake and allow to stand for 10 minutes. Measure the absorbance of the solution at 430 nm, Appendix II B, using water in the reference cell. The absorbance is not more intense than that produced in a solution prepared at the same time and in the same manner but using 1 mL of a solution in water containing 5 μg per mL of o-toluidine hydrochloride (0.75%, calculated as o-toluidine).
ASSAY
Carry out the method for liquid chromatography, Appendix III D, using the following solutions. Solution (1) contains 0.01% w/v of prilocaine hydrochloride BPCRS in the mobile phase. For solution (2) dilute the injection with the mobile phase to produce a solution containing 0.01% w/v of Prilocaine Hydrochloride.
The chromatographic procedure may be carried out using (a) a stainless steel column (15 cm × 4.6 mm) packed with end-capped octadecylsilyl silica gel for chromatography (5 μm) (Spherisorb ODS 2 is suitable), (b) a mixture of 30 volumes of 0.05M mixed phosphate buffer pH 8 and 70 volumes of methanol as the mobile phase with a flow rate of 1 mL per minute and (c) a detection wavelength of 240 nm.
Calculate the content of C13H20N2O,HCl in the injection using the declared content of C13H20N2O,HCl in prilocaine hydrochloride BPCRS.
