Researchers at Stanford University have developed a Jell-O-like conducting hydrogel that they claim feels and behaves similar to biological tissues but demonstrates the superior electrical conductivity of a metal or semiconductor. Quick and easy to fabricate, the material has demonstrated 'unprecedented electrical performance,' according to the researchers, and shows promise for use in future medical sensors.

To create the conductive gel, the researchers bound together long chains of the compound analine with a substance found naturally in plant tissues called phytic acid. And whereas current conductive polymers form a uniform film without the use of nanostructures, the cross-linked network resulting from the polymer chain binding yields a complex, sponge-like structure. It is this unique porous structure, the researchers note, that give the hydrogel its distinct electronic properties.

By expanding the gel's surface area, the pores increase the amount of charge that the material is capable of holding, the ability to sense chemicals, and the speed of electrical response. "Most hydrogels are tied together by a large number of insulating molecules, reducing the material's overall ability to pass electrical current. But phytic acid is a 'small-molecule dopant'–meaning that when it links polymer chains, it also lends them charge. This effect makes the hydrogel highly conductive," according to a Stanford story on the technology.

In addition to conductivity, the gel also offers the advantage of flexibility. Because the material does not solidify into a gel from a liquid form until the last step of its synthesis, it can be patterned onto surfaces using an inkjet printer or sprayed onto a substrate as a liquid and later converted to a gel. This capability could allow manufacturers to create intricately patterned electrodes at a low cost, according to the researchers.

Equipped with such flexibility and features, the gel could someday facilitate communication between biological systems and technological hardware. Potential applications include medical probes and biological sensors, among others.