Mianserin Tablets

General Notices

Action and use

Monoamine reuptake inhibitor; tetracyclic antidepressant.

Definition

Mianserin Tablets contain Mianserin Hydrochloride.

The tablets comply with the requirements stated under Tablets and with the following requirements.

Content of mianserin hydrochloride, C18H20N2,HCl

90.0 to 110.0% of the stated amount.

Identification

A. Shake a quantity of the powdered tablets containing 20 mg of Mianserin Hydrochloride with 10 mL of methanol, filter and evaporate the filtrate to dryness. The infrared absorption spectrum of the residue, Appendix II A, is concordant with the reference spectrum of mianserin hydrochloride (RS 234).
B. In the Assay, the chromatogram obtained with solution (2) shows a peak with the same retention time as that due to mianserin in the chromatogram obtained with solution (1).
C. The residue obtained in test A yields the reactions characteristic of chlorides, Appendix VI.

TEST

Related substances

Carry out the method for thin-layer chromatography, Appendix III A, using the following solutions prepared in a mixture of 1 volume of 13.5m ammonia and 4 volumes of methanol.

(1) Triturate a quantity of the powdered tablets containing 40 mg of Mianserin Hydrochloride with 2 mL of a mixture of 4 volumes of methanol and 1 volume of 13.5m ammonia and centrifuge. Use the supernatant.
(2) Dilute 1 volume of solution (1) to 200 volumes.
(3) Dilute 2 volumes of solution (2) to 5 volumes.
chromatographic conditions
(a) Use as the coating silica gel.
(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, dry in a current of cold air for 5 minutes and then expose to iodine vapour for 20 minutes.
mobile phase

10 volumes of methanol and 90 volumes of dichloromethane.

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) (0.5%) and not more than two such spots are more intense than the spot in the chromatogram obtained with solution (3) (0.2%).

Disregard any spot with an Rf value lower than 0.15.

Assay

Weigh and powder 20 tablets. Carry out the method for gas chromatography, Appendix III B. Use a 0.2% w/v solution of triphenylamine in toluene as the internal standard solution.

(1) Shake a quantity of the powdered tablets containing 60 mg of Mianserin Hydrochloride with 30 mL of 0.2m hydrochloric acid for 1 hour and filter. To 10 mL of the filtrate add 3 mL of 1m sodium hydroxide and 10 mL of internal standard solution, mix for 5 minutes, centrifuge and use the clear upper layer.
(2) Add 3 mL of 1m sodium hydroxide and 10 mL of internal standard solution to 10 mL of a solution containing 0.2% w/v of mianserin hydrochloride BPCRS in 0.2m hydrochloric acid, mix for 5 minutes, centrifuge and use the clear upper layer.
chromatographic conditions
(a) Use a fused silica column (30 m × 0.32 mm) bonded with a 0.25 µm film of poly(dimethyl)(diphenyl)siloxane (HP-5 is suitable).
(b) Use helium as the carrier gas at 1.0 mL per minute.
(c) Use isothermal conditions maintained at 255°.
(d) Use an inlet temperature of 280°.
(e) Use a flame ionisation detector at a temperature of 300°.
(f) Inject 1 µL of each solution.
(g) Use a split ratio of 1:5.

When the chromatograms are recorded under the prescribed conditions the retention time of triphenylamine relative to mianserin (retention time about 5 minutes) is about 0.7.

system suitability

The test is not valid unless, in the chromatogram obtained with solution (2), the resolution between the peaks due to triphenylamine and mianserin is at least 10.

determination of content

Calculate the content of C18H20N2,HCl in the tablets using the declared content of C18H20N2,HCl in mianserin hydrochloride BPCRS.

Storage

Mianserin Tablets should be protected from light.