Module 3 - Strategic case studies in practice

COLD RELIEF CAPSULES/GRANULES

METHOD OF TEST

4-AMINOPHENOL

REAGENTS AND STANDARDS

Mix together equal volumes of methanol and water.

Solvent mixture

4-Aminophenol Free Paracetamol

Re-crystallize paracetamol B.P. from water until it complies with the following test:- Dissolve 5 g of dried material in 100 ml solvent mixture, add 1 ml Alkaline Phenolic Sodium Phosphate solution. Mix and allow to stand for 30 minutes. No blue or green colour is produced. Dissolve 1 g trisodium orthophosphate, 1 g sodium hydroxide and 3 g phenol in, and make up to 50 ml with deionised water. Dissolve 0.03 g 4-Aminophenol in solvent mixture and dilute to 100 ml in an amber 100 ml volumetric flask. Pipette 10 ml of this solution into a second 100 ml flask and dilute to volume with solvent mix. Weigh twice the average weight into a 20 ml volumetric flask. Dilute to volume with solvent mixture, shake vigorously for 10 minutes. Filter through a NQ 4 filter paper. Pipette 10 ml into a Nessler cylinder. Into a second cylinder weigh 0.3 g 4-Aminophenol Free Paracetamol and dissolve in 10 ml solvent mixture, add 0.5 ml Standard Solution. To both tubes add 5 ml Alkaline Phenolic Sodium Phosphate solution. Allow to stand for 30 minutes. The_sample solution is no more intensely -coiat:lred -tl1ari. tl:le-5-ta.n.d.ai-cf. ---- -- -- --- - --

Alkaline Phenolic Sodium Phosphate Solution

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4.

Standard Solution (0.003% w/w)

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PROCEDURE

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