Principle: –
Vitamin C [ Ascorbic Acid ] is a fairly strong reducing agent and it is determined by simple titration with iodine solution which oxidizes ascorbic acid to dehydroascrbic acid. The iodine is reduced to iodide.
The excess of iodine is back titrated against standard sodium thiosulphate using starch as an indicator.
I2 + 2 Na2 S2 O3 ———->Na2 S4 O6 + NaI
Oxidation of ascorbic acid with iodine is reversible but proceeds in the forward direction in acid solution.
Requirements:-
1) Sample of vitamin C 2) Iodine solution 0.1 N 3) Sodium thiosulphate 0.1N
4) Starch solution.
Factor:- 1cc of 0.1 M Na2S2O3 == 0.0088 GM OF VIT. C
===================================================================
This website is a guide for pharmaceutical manufacturing and for pharmacy students and pharmaceutical regulatory affairs proffesionals and for every one associated with pharmaceutical industry , we recommend you to subscribe to this website by entering your email ID in the box provided so that you will receive our articles as and when our website is udated.
Following are some of articles which;will be useful for you in further understanding of aspects of sterile dosage form manufacturing