Researchers from ETH Zurich have developed a new hydrogel implant to repair severe bone fractures where traditional methods such as autografts or metal implants have disadvantages, including the need for further surgery or loss of stability[1][2][3]. The hydrogel consists of 97 percent water and 3 percent biocompatible polymer and mimics the softness of bone in the initial phase of healing[2][3]. Using a laser with two-photon microfabrication technology, bone-like structures are printed into it with a resolution of up to 500 nanometers, which is a thousand times thinner than a human hair[1][2][3]. The process achieves a world record in hydrogel structuring speed – up to 400 millimeters per second[1][2][3]. A specially designed binding molecule allows the laser-irradiated parts to solidify immediately, while the non-irradiated parts are washed out[2][3]. The hydrogel gradually dissolves in the body and promotes colonization by bone cells, thereby improving healing[1][2][3]. A study on this development was published in the journal Advanced Materials[3].