Tailored Biocompatible Polyurethane‐Poly(ethylene glycol) Hydrogels as a Versatile Nonfouling Biomaterial

Polyurethane‐based hydrogels are relatively inexpensive and mechanically robust biomaterials with ideal properties for various applications, including drug delivery, prosthetics, implant coatings, soft robotics, and tissue engineering. In this report, a simple method is presented for synthesizing and casting biocompatible polyurethane‐poly(ethylene glycol) (PU‐PEG) hydrogels with tunable mechanical properties, nonfouling characteristics, and sustained tolerability as an implantable material or coating. The hydrogels are synthesized via a simple one‐pot method using commercially available precursors and low toxicity solvents and reagents, yielding a consistent and biocompatible gel platform primed for long‐term biomaterial applications. The mechanical and physical properties of the gels are easily controlled by varying the curing concentration, producing networks with complex shear moduli of 0.82–190 kPa, similar to a range of human soft tissues. When evaluated against a mechanically matched poly(dimethylsiloxane) (PDMS) formulation, the PU‐PEG hydrogels demonstrated favorable nonfouling characteristics, including comparable adsorption of plasma proteins (albumin and fibrinogen) and significantly reduced cellular adhesion. Moreover, preliminary murine implant studies reveal a mild foreign body response after 41 days. Due to the tunable mechanical properties, excellent biocompatibility, and sustained in vivo tolerability of these hydrogels, it is proposed that this method offers a simplified platform for fabricating soft PU‐based biomaterials for a variety of applications. A simplified one‐pot method and inexpensive casting set‐up for fabricating and casting biocompatible polyurethane‐poly(ethylene glycol) (PU‐PEG) hydrogels from nontoxic commercially available reagents is presented. The resulting PU‐PEG materials have concentration‐modular mechanical properties, nonfouling characteristics, and sustained tolerability as an implantable material making them an attractive scaffold material for a variety of tissue‐engineering and drug delivery applications.