Bubble-based microrobots enable digital assembly of heterogeneous microtissue modules

Abstract

The specific spatial distribution of tissue generates a heterogeneous micromechanical environment that provides ideal conditions for diverse functions such as regeneration and angiogenesis. However, to manufacture microscale multicellular heterogeneous tissue modules in vitro and then assemble them into specific functional units is still a challenging task. In this study, a novel method for the digital assembly of heterogeneous microtissue modules is proposed. This technique utilizes the flexibility of digital micromirror device-based optical projection lithography and the manipulability of bubble-based microrobots in a liquid environment. The results indicate that multicellular microstructures can be fabricated by increasing the inlets of the microfluidic chip. Upon altering the exposure time, the Young’s modulus of the entire module and different regions of each module can be fine-tuned to mimic normal tissue. The surface morphology, mechanical properties, and internal structure of the constructed bionic peritoneum were similar to those of the real peritoneum. Overall, this work demonstrates the potential of this system to produce and control the posture of modules and simulate peritoneal metastasis using reconfigurable manipulation.

A review on microrobots driven by optical and magnetic fields

“…In addition, the bubble microrobot can be used to move and assemble microgel blocks consisting of living cells, with applications demonstrated for microtissue fabrication and studying cancer metastasis. 98,99 Fig. 5(g) shows an asymmetric microrobot structure, which was coated with a layer of light-absorbing material and sitting on a liquid–air interface.…”

Review of Bubble Applications in Microrobotics: Propulsion, Manipulation, and Assembly

“…Integrated assembly technology based on microbubbles provides a new solution for the manufacturing, assembly, and development of micro/nanostructures. Recently, Ge et al used these bubble microrobots to manipulate cell-loaded microstructures fabricated using a digital micromirror device (DMD)-based optical projection lithography system to form peritoneal tissue, which was similar to the biological peritoneum in terms of the mechanical properties, surface morphology, and internal microstructure [ 207 ]. The 3D operation and assembly method proposed by Dai et al have excellent application prospects for in vitro biological tissue construction, microassembly factories, and more.…”

Light-Controlled Microbots in Biomedical Application: A Review

“…In vivo implantation of such devices poses great difficulties, but these models help surgeons pre-plan for lifethreatening circumstances. Micro-tissue models fabricated using SLA were assembled digitally using bubble-propelled microbots [174]. The 3D stereolithographic technique was used to fabricate multi-material cantilevers that can mimic the native myocardium, with potential applications in sensor development and biohybrid actuators [175].…”