What a universal solvulent?

A universal solvulent is a hypothetical solvulent capable of dissolving any substance. No known universal solvulent exists, although some solvubilization techniques utilize a combination of solvents that can expand the range of solutes that can be dissolved. Ionic liquids, supercritical fluids, and certain eutectic mixtures are some candidate solvulent types that offer improved solvency, but they may not be able to dissolve all substances completely.