Action and use
Skeletal muscle relaxant.
Definition
Baclofen Tablets contain Baclofen.
The tablets comply with the requirements stated under Tablets and with the following requirements.
Content of baclofen, C10H12ClNO2
90.0 to 110.0% of the stated amount.
Identification
(1) Shake a quantity of the powdered tablets containing 20 mg of Baclofen with 20 mL of a mixture of 4 volumes of
absolute ethanol and 1 volume of
glacial acetic acid for 30 minutes and filter.
chromatographic conditions
(b) Use the mobile phase as described below.
(c) Apply 5 µL of each solution.
(d) Develop the plate to 15 cm.
(e) After removal of the plate, allow it to dry in air, spray with
ninhydrin solution and heat at 100° for 10 minutes.
mobile phase
20 volumes of glacial acetic acid, 20 volumes of water and 80 volumes of butan-1-ol.
confirmation
The principal spot in the chromatogram obtained with solution (1) corresponds to that in the chromatogram obtained with solution (2).
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
Dissolution
Comply with the requirements for Monographs of the British Pharmacopoeia in the dissolution test for tablets and capsules, Appendix XII B1.
test conditions
(a) Use Apparatus 2 and rotate the paddle at 50 revolutions per minute.
procedure
Carry out the method for liquid chromatography, Appendix III D, using the following solutions.
(1) After 45 minutes withdraw a 20 mL sample of the medium and filter through a membrane filter with a nominal pore size not greater than 0.45 µm, discarding the first 10 mL of filtrate.
chromatographic conditions
The chromatographic conditions described under Assay may be used.
determination of content
Calculate the total content of baclofen, C10H12ClNO2, in the medium from the declared content of C10H12ClNO2 in baclofen BPCRS.
Impurity A
Carry out the method for liquid chromatography, Appendix III D, using the following solutions in the mobile phase.
(1) Mix with the aid of ultrasound a quantity of the powdered tablets containing 0.1 g of Baclofen with 50 mL for 30 minutes, shaking occasionally to disperse the sample, and filter through a glass-fibre filter (Whatman GF/C is suitable).
chromatographic conditions
(b) Use isocratic elution and the mobile phase described below.
(c) Use a flow rate of 2 mL per minute.
(d) Use an ambient column temperature.
(e) Use a detection wavelength of 266 nm.
(f) Inject 20 µL of each solution.
mobile phase
5 volumes of glacial acetic acid, 440 volumes of methanol and 560 volumes of water, the mixture containing 0.182% w/v of sodium hexanesulfonate.
system suitability
The test is not valid unless, in the chromatogram obtained with solution (3), the resolution between the peaks due to baclofen and impurity A is at least 2.0.
limits
In the chromatogram obtained with solution (1) the area of any peak corresponding to baclofen impurity A is not greater than the area of the peak in the chromatogram obtained with solution (2) (2%).
Assay
Carry out the method for liquid chromatography, Appendix III D, using the following solutions.
(1) Add a quantity of whole tablets containing 0.1 g of Baclofen to 25 mL of a mixture of 1 volume of
glacial acetic acid and 100 volumes of
water and disperse with the aid of ultrasound. Dilute to 50 mL with
methanol, filter and use the filtrate.
chromatographic conditions
(b) Use isocratic elution and the mobile phase described below.
(c) Use a flow rate of 2 mL per minute.
(d) Use an ambient column temperature.
(e) Use a detection wavelength of 265 nm.
(f) Inject 20 µL of each solution.
mobile phase
0.01m sodium hexanesulfonate in a mixture of 1 volume of glacial acetic acid, 100 volumes of methanol and 100 volumes of water.
system suitability
The test is not valid unless, in the chromatogram obtained with solution (3), the resolution between the peaks due to baclofen and impurity A is at least 7.0.
determination of content
Calculate the content of C10H12ClNO2 in the tablets using the declared content of C10H12ClNO2 in baclofen BPCRS.