Gibberellic Acid not working on seeds

Ok so have been having trouble trying to germinate these seeds so I bought some GA3/GibberellicAcid.
For some reason it's not doing any thing to my seeds, I have tried 100ppms to 500 ppms and still nothing what am i doing wrong any advise is greatful.

It may just be bad seed.. I've heard people rave about GA3 and I've always wanted to give it a try!

Thanks for the reply I think all the seeds are dead or they are under developed .

The seeds turn black and then don't germinate