An Efficient Thermal Elimination Pathway toward Phosphodiester Hydrogels via a Precursor Approach

Abstract

Phosphodiester hydrogels offer a wide range of fascinating properties. Not only do they exhibit excellent hemocompatibility and cellular compatibility, they also show a remarkable resistance to protein adsorption, thereby limiting the foreign body response. In this work, phosphodiester-crosslinked hydrogels are produced by a simple free-radical polymerization of a phosphotriester crosslinker. In a second step, this material is transformed to the phosphodiester, by heating it up to 60 degrees C in phosphate-buffered saline. Compared to earlier methods, there is no need for acids, bases, or oxidizing agents to achieve this final conversion to the phosphodiester. This method thus reduces the risk to damage or degrade any sensitive biomolecules that might be of interest to tissue engineers, such as various growth factors or other proteins. The phosphotriester crosslinker is readily synthesized out of common laboratory chemicals in multigram quantities with good yield and easy workup and purification.