What is the advantage of using DAD detector?

[moonchips]

Greetings.

I am working on developing a method to determine antioxidants leachables. I tested our drug and found some unknown peaks with relatively large peak area. I was suggested to use DAD detector to figure it out if the unknowns are similar compounds as antioxidants. But DAD detector can not give too much qualitative information. In another words, it is not as good as MSD to identify unknowns.

Is it posisble for me to solve this problem without MSD?

By the way, do anyone know FDA's requirement on unknown? Say How many mcg/kg/day?

thanks
have a good weekend

[Anthony Crawshaw]

By using the DAD you should at least get an indication of the similarity of the unknowns to the compound of interest through their respective UV absorbance spectra.

As for the limits of unknowns. I would suggest looking at ICH Q3A (R2) and Q3B (R2) Impurties in New Drug Substances and Drug Products. These should match any FDA requirements. www.ICH.org

[moonchips]

Anthony Crawshaw
Thanks a lot!

Is DAD detector mainly useful in the purity analysis? Hence it is useful to decide integration parameters, right?