Action and use
Local anaesthetic.
DEFINITION
Mepivacaine Injection is a sterile solution of Mepivacaine Hydrochloride in Water for Injections.
The injection complies with the requirements stated under Parenteral Preparations and with the following requirements.
Content of mepivacaine hydrochloride, C15H22N2O2,HCl
95.0 to 105.0% of the stated amount.
IDENTIFICATION
A. Carry out the method for thin-layer chromatography, Appendix III A, using a TLC silica gel F254 plate and a mixture of 1 volume of 13.5M ammonia, 5 volumes of methanol and 100 volumes of ether as the mobile phase, but allowing the solvent front to ascend 12 cm above the line of application. Apply separately to the plate 10 μL of each of the following solutions. For solution (1) dilute a quantity of the injection with sufficient ethanol (96%) to produce a solution containing 0.4% w/v of Mepivacaine Hydrochloride. Solution (2) contains 0.4% w/v of mepivacaine hydrochloride BPCRS in ethanol (96%). Solution (3) contains 0.4% w/v of each of mepivacaine hydrochloride BPCRS and lidocaine hydrochloride BPCRS in ethanol (96%). After removal of the plate, allow it to dry in air and examine under ultraviolet light (254 nm). The principal spot in the chromatogram obtained with solution (1) is similar in position and size to the principal spot in the chromatogram obtained with solution (2). The test is not valid unless the chromatogram obtained with solution (3) shows two clearly separated principal spots.
B. In the Assay, the chromatogram obtained with solution (1) shows a peak with the same retention time as the principal peak in the chromatogram obtained with solution (2).
TESTS
Acidity
pH, 4.5 to 6.0, Appendix V L.
2,6-Dimethylaniline
Carry out the method for liquid chromatography, Appendix III D, using the following solutions. For solution (1) dilute a quantity of the injection containing 0.1 g of Mepivacaine Hydrochloride to 100 mL with the mobile phase. Solution (2) contains 0.0002% w/v of 2,6-dimethylaniline in the mobile phase.
The chromatographic procedure described under Assay may be used.
In the chromatogram obtained with solution (1) the area of any peak corresponding to 2,6-dimethylaniline is not greater than the area of the principal peak in the chromatogram obtained with solution (2) (0.2% of the content of mepivacaine hydrochloride).
ASSAY
Carry out the method for liquid chromatography, Appendix III D, using the following solutions. For solution (1) dilute a quantity of the injection containing 0.1 g of Mepivacaine Hydrochloride to 100 mL with the mobile phase and dilute 1 volume of this solution to 20 volumes with the mobile phase. Solution (2) contains 0.005% w/v of mepivacaine hydrochloride BPCRS in the mobile phase.
The chromatographic procedure may be carried out using (a) a stainless steel column (25 cm × 3.2 mm) packed with octadecylsilyl silica gel for chromatography (5 μm) (Spherisorb ODS 1 is suitable), (b) as the mobile phase with a flow rate of 0.5 mL per minute a mixture of 1 volume of triethylamine, 400 volumes of acetonitrile and 600 volumes of a 0.2% w/v solution of potassium dihydrogen orthophosphate, the mixture adjusted to pH 4.0 with orthophosphoric acid and (c) a detection wavelength of 212 nm.
Calculate the content of C15H22N2O2,HCl,HCl in the injection using the declared content of C15H22N2O2,HCl,HCl in mepivacaine hydrochloride BPCRS.
