Picture: YOKOHAMA National University
A research team at Yokohama National University has developed a new method for controlling the orientation of collagen fibers in biological tissue models. The method is based on flow-controlled orientation within microfluidic channels produced by 3D printing. The results were published in ACS Biomaterials Science and Engineering on May 12, 2025.
Collagen is a central structural protein of the body that provides mechanical stability in tissues such as the skin, bones or cornea. Not only the presence, but above all the orientation of the collagen fibers plays a decisive role in the functionality of the tissue. Previous methods for creating oriented structures, for example using magnetic fields or electrospinning, are either contaminated with residual materials or require problematic solvents. The method now presented does not require these aids.
“By using a technique that uses flow to orient collagen fibers and cells, it is possible to fabricate complex oriented tissues with multiple directions in flow channels constructed using a 3D printer,” said Kazutoshi Iijima, associate professor at YOKOHAMA National University and author of this study.
Through the targeted use of flows in a 3D-printed mold, both collagen fibers and embedded cells such as fibroblasts can be aligned in the desired direction. To do this, the researchers used a type I collagen solution in combination with cells that were guided through microfluidic channels. Depending on the geometry and direction of flow, this created multi-dimensionally oriented structures that can mimic the structure of complex tissues such as skin or skull bones.
“This system will lead to the customization of tissue-specific models using fine, multidirectionally oriented biomaterial scaffolds for the preparation of various oriented biological tissues,” said Shoji Maruo, author of the study and professor at YOKOHAMA National University.
Using this method, biomimetic scaffolds can be produced with high precision. The aim is to develop application-specific tissue models for in-vitro research and possible transplantation scenarios. The process opens up new approaches in regenerative medicine and the bioadditive production of complex structured tissue.
