Phenylbutazone (Finished product) Assay (By UV)
Sample Preparation: Weigh about powder equivalent to 500 mg of Phenylbutazone and shake vigorously with 150 ml of 0.1 M sodium hydroxide for 45 minutes. Add sufficient 0.1M sodium hydroxide to produce 250.0 ml, mix and filter, rejecting the first 20 ml of the filtrate.
To 5.0 ml of the filtrate add 50 ml of water and 4 ml of hydrochloric acid and extract with three quantities, each of 30 ml, of ether. Combine the ether extracts and extract with three quantities, each of 30 ml, of 0.1M sodium hydroxide. Combine the aqueous extracts, pass nitrogen through the solution to remove the residual ether and add sufficient 0.1M sodium hydroxide to produce 100.0 ml and mix well.
To 10.0 ml of this solution add sufficient 0.1M sodium hydroxide to produce 100.0 ml.
Standard
Preparation: Weigh
about 0.5 g of phenylbutazone WS
and shake vigorously with 150 ml of 0.1 M sodium hydroxide till dissolve. Add
sufficient 0.1M sodium hydroxide to
produce 250.0 ml and mix.
To 5.0 ml of this solution add
sufficient 0.1M sodium hydroxide to
produce 100.0 ml and mix well.
To 10.0 ml of this solution add sufficient 0.1M sodium hydroxide to produce 100.0 ml.
Measure the absorbance of sample solution and standard solution at the maximum at about 264 nm, using 0.1M sodium hydroxide as the blank.
Calculate the content of phenylbutazone by comparison of sample and standard.
Calculations:
