Chromatography Forum

Posted: **Sat Jun 28, 2008 10:41 am**

Hi, I have a water insoluble drug substance that I have to stress with 1 N hcl (according protocol). As drug substance is insoluble I will first dissolve in a suitable solvent.

However, if I mix 5 ml drug substance in solution+5 ml of 1 N HCl then the normality of the HCL is only 0.5 N.

Or should I mix 5 mL of drug substance solution with 5 ml of 2 N HCl so that the final normality is 1N.

Also is it necessary to run system suitablity when doing forced degs which will be based on purity rather than assay.

Please help
Scio

Posted: **Sat Jun 28, 2008 4:39 pm**

My interpretation is that the final concentration should be 0.1 N.

If you are running a validated method, then system suitability is part of that method and must be run.

Posted: **Sat Jun 28, 2008 6:15 pm**

thanks Tom

Posted: **Sun Jun 29, 2008 2:21 am**

Oops! I should have written 1 N (hopefully, the meaning was evident from context!)