light throughout the st, Crush one fablet and tränsfer to a centrifuge tube with the aid of 10 ml of ethanol. Shake for 30 minutes, centrifuge and dec

A: To a quantity of the powdered tablets equivalent to 10 mg of Colchicine add 20 ml of water and mix well. Filter into aseparating funnel and extract with 30 ml of chlorotorm. Evaporate the chloroform extract to dryness using moderate heat. The intra-red absorption spectrum, Appendix 5.4, of the residue is concordant with the reterence spectrum of colchicine or with the spectrum obtamed from colchicine RS. B: To a quantity of the powdered tablets equivalent to 1 mg of Colchicine add 0.2 ml of sulphuric acid and mix; ayellow colour is produced. On adding a drop of nitric acid the colour changes to greenish-blue then reddish and finally almost colourless. ön the addition of an excess of 5M sodium hydroxide the colour changes to red. Related substances: Comply with the test descnbed under Colchicine using the following Solutions. For solution (1) extract a quantity of the powdered tablets equivalent to 5 mg of Colchicine with 5 ml of Chloroform ,filter and evaporate the filtrate to dryness in a current of air. Dissolve the residue äs completely äs possible in 0.1 ml of ethanol (95%), centrifuge and use the supernatant liquid. For solution (2) dilute 1 volume of solution (1) to 20volumes with ethanol (95%) Uniformity of confent: Comply with the requucments stated under Tablets using the following inethod of analysis, protecting the Solutions from light throughout the st, Crush one fablet and tränsfer to a centrifuge tube with the aid of 10 ml of ethanol. Shake for 30 minutes, centrifuge and decant the supernatant liquid. Wash the residue with small quantities of ethanol. combine the extract and washings and add sufficient ethanol to produce a solution containing 0.001 %w/v of Colchicine. Measure the absorbance of the resulting solution at the maximum at about 350 nm. Appendix 5.5. Calculate the content of C22H25NO6 taking 425 äs the value of A(1%,1cm) at the maximum at about 350 nm. öther requirements: Comply with the requirements of tests stated under Tablets. Assay: Protect the Solutions from light throughout the test. Weigh and powder 20 tablets. Weigh accurately a quantity of the powder equivalent to 0.5 mg of Colchicine, add 10 ml of ethanol and shake for 30 minutes. Centrifuge and decant the supernatant liquid. Wash the residue with small quantities of ethanol and mix the extract and washings. Add sufficient ethanol to produce 50.0 ml and mix well. Measure the absorbance of the resulting solution at the maximum at about 350 nm, Appendix 5.5. Calculate the content of C22H25NC6 takmg 425 äs the value of A(1%,1cm) at the maximum at about 350 nm. COLCHICINE AND PROBENECID TABLETS Category: Uricosurc agent. Dose: Colchicine, 1