Conductive liquid, that after evaporation will allow me to use my gloves with a smartphone

I'm looking for a conductive liquid that, after it evaporates, leaves the material that has been exposed to it conductive. 


I'd like to use my smartphone with gloves. I do have a pair of professional, expensive gloves, with "smartphone friendly material" on the index finger-pad, but it works dreadfully. I'd like to use the tip of my finger, and not the finger-pad, to interact with the smartphone surface.


So I thought, let's wet the material in some conductive liquid, let it dry, and done!


I did try this approach with colloidal silver and it does not seem to work.


The next on my list is a solution of water with iron rust ( I am unsure about the effect, but I'd give it a try).


Any other ideas? It must be human-safe. Colloidal silver would be perfect (antibacterial properties) if it could be made to work.


