Assay: Determined by liquid chromatography.
Weigh and powder 20 tablets. Weigh a quantity of the powder containing 0.2 g of Ornidazole, transfer to a sintered glass crucible and extract with 10ml of hot acetone. Repeat the extraction 6 times with hot acetone. Cool, add to the combined extracts 50ml of acetic anhydride. Titrate with 0.1 M perchloric acid, determining the end point potentiometricaaly. Carry out the blank titration.
1ml of 0.1 M perchloric acid is equivalent to 0.02196g of Ornidazole.
Alternative Method: By UV Spectrophotometer
Test Solution: Weigh and powder 20 tablets. Weight sample equivalent to 100mg of Ornidazole 100ml volumetric flask add 20ml 0.1 M HCl into it and sonicate to dissolve the test sample. Make up to mark with 0.1 M HCl. Filter and dilute 1ml of this solution to 50ml in 0.1 M HCl.
Reference Solution: Weigh 100mg of reference standard of Ornidazole in 100ml of volumetric flask. Add 20ml 0.1 M HCl into it and sonicate to dissolve. Make up to mark with 0.1 M HCl. Dilute 1ml of this solution to 50ml with 0.1 M HCl.
Check Absorbance of test as well as reference standard at about 277nm in UV Spectrophotometer.
Calculate the content of Ornidazole in the tablets.
Formula:
Abs. of Test STD Wt.(mg) 1 100 50 Potency
—————–X————–X———X—————–X——-X———–X Average wt.
Abs. of STD 100 50 Test Wt.(mg) 1 100
