Is there a difference between distilled and deionized water?

I am doing synthesis of nanoparticles of Ag and I am still using distilled water to prepare a solution of AgNO3. But because the distilled water ran out I used deionized. For almost 2 days after, I observed a very tiny coloration (purple) of my solution (it was completely transparent with distilled water)
I don't know if it's be possible? (the change of color)
or did something else happen?