Validation of a method

[Tequila]

Dear members of this forum,

Recently I have been looking for a dissolution test to flurazepam tablets.
The first choice was HCl 0.1 N and I prepared a standard in this solvent when I injected I looked an important peak before the main peak (I suppose is degradation product of the drug), the area of flurazepam decreased with the time and after 1 hour this value not decreased more.
I tried with water and the standard chromatogram showed only one peak at 225 nm but the solubility of the drug in this solvent is very poor .
Someone had similar problem in the past, I would like to know ours experiences. Some months ago I have the some problems with bromazepam tablets (6 mg per tablet) in HCl 0.1 N and I decided to prepare the final standard 1 hour before the measure because the absorbance in each individual vessel not change with the time but the absorbance in the standard solution decreased until certain value and the Dissolution percent is good refer to our acceptance level (80 %).
Thanks a lot for your invaluble help,

Diego

[Tequila]

Dear members of this list,

I had a mistake the drug which I had problem is flunitrazepam and not flurazepam.
Thanks in advance for your help,

Diego

[Lime]

Dear Diego,

You may try a new solvent which is your API is stable and soluble. If you are developing a new dissolution method, you should try at least three different solution anyway so, you can check the solubility and solution stability in those medias.

hope helps,

lime