Fluids are usually not accepted as lynchpins, for a few reasons. Making a lynchpin involves lifting, handling and manipulating it, and that's hard in a fluid. A "damaged" lynchpin also stops functioning, so how do you define this in a fluid? It constantly evaporates, leaves parts of itself behind on surfaces, etc... other lynchpin can work to the same effect though.
So yes, I suppose you could do this. As long as Energy Aura does not exist in SR5 it remains a house rule, but other than that...