3D Printing of Noncytotoxic High-Resolution Microchannels in Bisphenol-A Ethoxylate Dimethacrylate Tissue-Mimicking Materials.

The ability to create cell-laden fluidic models that mimic the geometries and physical properties of vascularized tissue would be extremely beneficial to the study of disease etiologies and future therapies, including in the case of cancer where there is increasing interest in studying alterations to the microvasculature. Engineered systems can present significant advantages over animal studies, alleviating challenges associated with variable complexity and control. Three-dimensional (3D)-printable tissue-mimicking hydrogels can offer an alternative, where control of the biophysical properties of the materials can be achieved. Hydrogel-based systems that can recreate complex 3D structures and channels with diameters <500 μm are challenging to produce. We present a noncytotoxic photo-responsive hydrogel that supports 3D printing of complex 3D structures with microchannels down to 150 μm in diameter. Fine tuning of the 3D-printing process has allowed the production of complex structures, where for demonstration purposes we present a helical channel with diameters between 250 and 370 μm around a central channel of 150 μm in diameter in materials with mechanical and acoustic properties that closely replicate those of tissue. The ability to control and accurately reproduce the complex features of the microvasculature has value across a wide range of biomedical applications, especially when the materials involved accurately mimic the physical properties of tissue. An approach that is additionally cell compatible provides a unique setup that can be exploited to study aspects of biomedical research with an unprecedented level of accuracy.