Document Type
Article
Publication Date
6-8-2020
Abstract
Neural implants that are based on mechanically adaptive polymers (MAPs) and soften upon insertion into the body have previously been demonstrated to elicit a reduced chronic tissue response than more rigid devices fabricated from silicon or metals, but their processability has been limited. Here we report a negative photoresist approach towards physiologically responsive MAPs. We exploited this framework to create cross-linked terpolymers of 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate and 2-ethylhexyl methacrylate by photolithographic processes. Our systematic investigation of this platform afforded an optimized composition that exhibits a storage modulus E′ of 1.8 GPa in the dry state. Upon exposure to simulated physiological conditions the material swells slightly (21% w/w) leading to a reduction of E′ to 2 MPa. The large modulus change is mainly caused by plasticization, which shifts the glass transition from above to below 37 °C. Single shank probes fabricated by photolithography could readily be implanted into a brain-mimicking gel without buckling and viability studies with microglial cells show that the materials display excellent biocompatibility.
Publication Title
Journal of Materials Chemistry B
Rights
© 2020 The Authors. This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence: http://creativecommons.org/licenses/by-nc/3.0/
Recommended Citation
Christoph Weder et al. Mechanically adaptive implants fabricated with poly(2-hydroxyethyl methacrylate)-based negative photoresists. . Mater. Chem. B, 2020, 8, 6357. https://doi.org/10.1039/D0TB00980F