best airbrush medium for Paper artwork?



I am asking this one because I would like to store my artwork in Itoya Portfolios. that means using some kind of paper or illustration board instead of a aluminum sheet or something else.. what airbrush medium would work best for this. I know some artists have used other stuff besides airbrush paints. Like water color and acrylics. what kind of paper or art board would you suggest for what I would like to do? and what kind of paint?
as far as paper goes Shoellershammer 6G is the best for me , paint is personal I like etac efx paints and it is the only paint I use on paper