Reagent
:
1) Ninhydrin solution: 1.5 % w/v
solution Ninhydrin in (Pyridine : methanol 1:1 )
2) Ascorbic acid solution: 0.05% w/v
Ascorbic acid solution.
Sample Solution: Weigh the 20 Capsules. Take the powder equivalent to 5 mg of Phenylephrine Hydrochloride in 100 ml volumetric flask dissolved 50 ml with water shake with 15 minutes and make the volume 100 ml with water and Filter. Take filtrate as sample solution.
Procedure: Take
2 ml of standard and sample solution & water for blank in three different
25 ml of volumetric flask, add 1 ml of ascorbic acid solution and 2 ml of
ninhydrin solution.
Place the three 25 ml of volumetric flask in boiling water bath
for 25 minutes, cool in ice cold and dilute 25 ml with water.
Take reading on suitable spectrophotometer at 570 nm.
Spl rdg x Wt
of std x 5 x 100 x Avg wt x Std purity x 100
Std rdg x 100 x 100 x wt
of Spl x 100 x L. A.
