Porous Hybrid Soft Actuators From Liquid Crystal Networks and Lyotropic Chromonic Liquid Crystal Templated Hydrogels

Liquid crystal networks (LCNs) have shown great utility in soft robotics as artificial muscles. Yet, their potential in biomedical applications, such as drug delivery, remains largely untapped. This can be partly attributed to LCNs' limited compatibility with biological environments, and non-porous microstructure and morphology. The current study focuses on developing actuators with improved porosity by creating constructs based on LCNs hybridized with liquid crystal hydrogels (LCHs). In our design, LCNs provide mechanical integrity and stimuli-responsiveness, while LCHs introduce structural porosity and precise control over deformation. To manipulate LCHs' microstructure and program the deformation of hybrid actuators, we used magnetically aligned lyotropic chromonic liquid crystals (LCLC) derived from disodium cromoglicate (DSCG) to template desired morphologies in acrylamide (AAM)-based LCHs. Our results revealed that the integration of LCHs into LCNs dramatically increases the porosity of the construct. Interestingly, the distinct alignment and stimuli-responsiveness of LCN and LCH layers can be leveraged to obtain complex programmable deformation. We believe that the inherent porosity and biocompatibility of LCHs can be used to expand the application of LCNs in therapeutic delivery and in enabling safer interaction with biological tissues, positioning them as promising materials for use in minimally invasive medical devices and adaptive implants.