Question
Posted on: March 6 2013How do we keep menthol in solution in the following preparation: Boric acid powder 5.925 g Menthol 2.275 g (a)
Aqua Dist. AD 250ml < br/> Solution stays clear up to 150ml, with further addition of water a slight cloudy emerges.
Answer
More than likely the turbid is due to menthol, which does not completely dissolve. The most obvious solution is to increase the amount of isopropanol. But the quantity, which we can add, is not unlimited. Perhaps it is better to do something to keep the menthol in solution through Solubilisation. Therefore, I would suggest adding 3g Tween 80.
I would prepare the solution by dissolving boric acid and Nalauryl Sulfate in 100 ml of water if necessary. Menthol is dissolved in the Mensgsel isopropanol and propylene glycol together with the Tween 80 3g. The aqueous solution is slowly added to this solution under stirring. Then it is diluted to 250ml.
I would prepare the solution by dissolving boric acid and Nalauryl Sulfate in 100 ml of water if necessary. Menthol is dissolved in the Mensgsel isopropanol and propylene glycol together with the Tween 80 3g. The aqueous solution is slowly added to this solution under stirring. Then it is diluted to 250ml.