Metal studs can be used. For extra support isolators can be used to support the walls off the existing walls. After the walls are done, you can then build your floating floor as mention above. The last step to a floated room is the ceiling. The ceiling must be suspended of building isolators.
Black iron is used for strength.
Then a frame of metal studs is attached to the black iron. Then as a final precaution, wherever a wall meets a floor or ceiling, that area is caulked. As you can see from my diagram, a floated room is a room within a room. Now of course there are other things to consider. Air conditioning vents and electric work.