CAPTOPRIL TABLETS Usual strengths: 12.5 mg, 25 mg, 50 mg. Storage Store in tightly-closed containers. STANDARDSCaptopril Tablets

substance being examined and (2) 0.4% w/v of captopril RS. After removal of the plate, allow it to dry in air and spray with a freshly prepared mixture of 1 volume of strong ammonia solution and 6 volumes of a 0.04% w/v solution of 5,5'-dithiobds(2-nitrobenzoic acid) in methanol and allow to stand for 5 minutes. The principal band in the chromatogram obtained with solution (1) corresponds to that in the chromatogram obtained with solution (2).C: Melts between 104° and 110°, Appendix 8.8 Specific optical rotation: Between-125° and-134°, determined in a 1 % w/v solution in ethanol, Appendix 8.9. Heavy metals: Not more than 30 ppm, determined on 0.66 g by Method B, Appendix 3.12 Sulphated ash: Not more than 0.2%, Appendix 3.22. Loss on drying: Not more than 1.0%, determined on 1 g by drying at 600 at a pressure not exceeding 0.7 kPa, Appendix 8.6 Assay: Weigh accurately about 0.3 g, dissolve in 100 ml of water in a stoppered-flask, add 10 ml of 1.8M sulphuric acid and 1 g of potassium iodide. Titrate with 0.025M potassium iodate using 3 ml of starch solution, added towards the end-point, as indicator. Each ml of 0.025M potassium iodate is equivalent to 0.03308 g of C9H15NO3S. CAPTOPRIL TABLETS Usual strengths: 12.5 mg, 25 mg, 50 mg. Storage Store in tightly-closed containers. STANDARDSCaptopril Tablets contain not less than 90.0 per cent and not more than I 10.0 per cent of the stated amount of captopril, C9H15NO3S Identification: A: Comply with test B described under Captopril, using as solution (1) the clear supernatant liquid obtained by extracting the powdered tablets equivalent to 100 mg of Captopril with 25 ml of methanol and centrifuging. Dissolution: Comply with the dissolution test far tablets and capsules. Appendix 7.3, using Apparatus 2, as the medium 900 ml of 0.1M hydrochloric acid and rotating the basket at 50 rpm for 20 minutes. Withdraw a suitable volume of the sample and filter. Measure the absorbance of the filtrate, suitably diluted with the dissolution medium, if necessary, at the maximum at about 212 nm. Appendix 5.5. Calculate the content of CGH15NO3S in the medium from the absorbance obtained from a solution of known concentration of captopril RS in the same medium and from the declared content of C9H15NO3S in captopril RS.D: Not less than 80% of the stated amount of C9H15NO3S. Other requirements: Comply with the requirements of tests stated under Tablets. Assay. Protect the solutions from exposure to air and use within 8 hours of preparation. Carry out the method for high performance liquid chromatography. Appendix 4.3, using the following solutions. For solution (1) dissolve a quantity of the finely powdered tablets equivalent to about 25 mg of Captopril in 25 ml of the mobile phase by ultrasonic treatment for 15 minutes, centrifuge and use the clear supernatant liquid Solution (2) contains 0.1% w/v of captopril RS in the mobile phase. Carry out the chromatographic procedure using (a) a stainless steel column (25 cm x 4.6 mm) packed with stationary phase LCI, (b) a degassed mixture of 55 volumes of methanol and 45 volumes of water containing 0.05 volume of phosphoric acid as the mobile phase with a flow rate of 1 ml per minute and (c) a detection wavelength of about 220 nm. Calculate the content of C9H15NO3S from the declared content of C9H15NO3S in captopril RS CARAMEL Burnt Sugar Caramel is a concentrated solution of the product obtained by