Ultraviolet laser processing is a promising technology for developing the complex microstructures needed to build life-like biohybrid actuators and enabling complex alignment of muscle cells, as shown by Tokyo Tech researchers. Compared to traditional complex methods, this innovative technique allows for the easy and rapid fabrication of microstructures with complex patterns to achieve a variety of muscle cell arrangements, paving the way for biohybrid actuators capable of complex and flexible movements.
Biomimetic robots, which mimic the movements and biological functions of living organisms, are an attractive field of research that can not only lead to more efficient robots but also serve as a platform for understanding muscle biology. Among these, biohybrid actuators, which are composed of soft materials and muscle cells that can reproduce the force of actual muscles, have the potential to realize realistic movements and functions such as self-healing, high efficiency, and high power-to-weight ratio. This is a ratio that would be difficult for traditional bulky robots that require heavy energy sources. One way to achieve such life-like movements is to arrange muscle cells in an anisotropic manner in biohybrid actuators. This involves aligning them in specific patterns that face different directions, such as those found in living organisms. Previous studies have reported biohybrid actuators with significant movements using this technology, but they mainly focused on anisotropic alignment of muscle cells in straight lines, allowing only simple movements, as opposed to complex movements of native muscle tissue, such as twisting, bending, and bending. I brought it. And contractions. Real muscle tissue has a complex arrangement of muscle cells, including curved and spiral patterns.
Creating these complex arrays requires the formation of curved microgrooves (MGs) in the substrate, which serve as guides to align the muscle cells into the required pattern. Fabrication of complex MGs has been achieved by methods such as photolithography, wave microscopy, and microcontact printing. However, these methods involve several complex steps and are therefore not suitable for rapid fabrication.
To solve this, a research team led by Associate Professor Toshinori Fujie of the School of Life Sciences and Technology at Tokyo Tech, Japan, developed an ultraviolet (UV) laser processing technology to fabricate complex microstructures. . “Building on our previous prototypes, we demonstrate that a biohybrid actuator using SBS (hard rubber) thin films with randomly anisotropic MGs fabricated by UV laser treatment can control cell alignment in arbitrary anisotropic directions, resulting in more life-like flexible movements. “We hypothesized that it could be reproduced.” Dr. Fujie explains. Their research was published in the journal Biomanufacturing.
The new technology involves forming curved MGs in polyimide via UV laser processing and then transferring them to thin films made of SBS. Next, skeletal muscle cells called myotubes found in living organisms are aligned using MG to obtain an anisotropic curved muscle pattern. Researchers used this method to develop two different biohybrid actuators. One is connected to the glass substrate and the other is not connected. Upon electrical stimulation, both actuators deformed through a torsional-like motion. Interestingly, when untethered, the biohybrid actuator transformed into a 3D free-standing structure due to the curvilinear alignment of the root canal, like a natural sphincter.
“These results imply that compared to conventional methods, UV laser cones are a faster and easier way to fabricate tunable MG patterns. This method presents an exciting opportunity to achieve more life-like biohybrid actuators through guided alignment of root canals. provides.,” Dr. Fujie said, emphasizing the potential of this innovative technology.
Overall, this study demonstrates the potential of UV laser processing for fabricating diverse anisotropic muscle tissue patterns, paving the way for more life-like biohybrid actuators capable of complex and flexible movements!