Apparatus No. 1,
Medium. 900 ml of 0.1 M hydrochloric acid,
Speed and time. 50 rpm and 30 minutes.
Solvent mixture. To about 50 ml of methanol in a 100.0 ml volumetric flask add 2 ml of hydrochloric acid, dilute with methanol to volume, and mix.
Reference solution. Dissolve about 35 mg of albendazole RS, in 5 ml of solvent mixture and dilute to 100.0 ml with 0.1 M hydrochloric acid. To 5.0 ml of this solution, dilute to 200.0 ml with 0.1 M sodium hydroxide.
Withdraw a suitable volume of the medium, filter and dilute with 0.1 M sodium hydroxide, if necessary. Measure the absorbance of the solution at the maximum and minimum absorbance at 308 nm and 350 nm (2.4.7) using 0.1 M sodium hydroxide as the blank. Similarly measure the absorbance of a solution of known concentration of albendazole RS. Calculate the content of C12H15N3O2S in the medium.
- Not less than 80 per cent of the stated amount of C12H15N3O2S.