Curling of Gel Scaffold Layer for Cell Culture by a Deformable Microactuator Mat Toward Biological Canal Formation

A gel scaffold for a biological canal is formed using a deformable soft microactuator mat. Three-dimensional cellular tissue structures are important for organ-on-a-chip in in-vitro biomimetic models. However, most traditional cellular tissues have been cultured in a dish or transwell. Furthermore, cellular culture on the inner wall of pre-manufactured channels has been recently reported. In this study, we propose a deformable actuator mat that can transform a flat structure into a tubular structure. The active mat, which is composed of pneumatic balloon actuator arrays, assembles a biological canal from a flat sheet of a gel scaffold for cell culture. The mat can return to its initial flat state so that the gel-based canal structure with cells can self-stand. A self-standing tubular gel structure is demonstrated as a biomimetic canal toward a biological canal with cells. A self-standing tubular gel structure has permeability, which is important for evaluation of pharmacokinetics. The actuator mat under the gel layers was curled into a tubular shape (approximately 1 mm diameter) and returned after the assembly. Culturing cellular tissues on a demonstrated gel structure will reproduce the biological permeability of organs such as an intestinal tract. This study confirms the gel-based canal formation process without cells as a feasibility study. The proposed technique has potential for the flexible design of biological three-dimensional structures, thereby contributing to pharmacokinetics research.