By
Titration Method:
Weigh
20 Capsules From a quantity of the mixed contents of 20 capsules weigh
accurately a quantity of the powder equivalent to 0.5 g of Ibuprofen, extract
with 60 ml of chloroform for 15 minutes and filter. Wash the residue with three
quantities, each of 10 ml, of chloroform and gently evaporate the filtrate just
to dryness in a current of air. Dissolve the residue in 100 ml of
ethanol (95%), previously neutralized to phenolphthalein solution, and titrate
with 0.1M sodium hydroxide using phenolphthalein solution as indicator.
Each
ml of 0.1M sodium hydroxide s equivalent to 0.02063 g of C13H18O2.
Calculation:
Mg/Capsule
=
Spl redg x Actul Molarity x 0.02063 x 1000 x Avg Net content
sample wt (gm) x 0.1
Mg /Capsule x100
% = -------------------------
Labeled Claim
