Crimped Fiber Printing via E-Jetting for Tissue Engineering

A regular pattern called crimp is an essential morphological feature of collagen fibers in native tendon. In this study, the direct crimp writing (DCW) and zig-zag pattern writing (ZPW) were developed based on electrohydrodynamic jet printing (E-jetting) process to fabricate the crimped fibers. For the DCW process, the fibers were deposited with the linear movement of stage, and the crimps (crimp angle: ∼ 46°; crimp length: ∼630 μm; fiber diameter: ∼100 μm) were formed from the spinning of fibers. For the ZPW process, the fibers was printed via the zig-zag moving path, and the effects of a vital process parameter (i.e. dwell time) on the fiber characteristics were investigated to obtain controllable and regular crimped fibers. The result of mechanical testing showed that the ZPW fibers exhibited the “toe” and linear regions with different Young’s modulus (4 ± 1 MPa and 23 ± 4 MPa, respectively), while DCW fibers were found only with linear region. Compared with DCW process, the ZPW process was able to fabricate crimped fibers in a more controllable pathway. The human tenocytes were also seeded on the ZPW fibers to investigate the cellular alignment. This study suggested that ZPW process was capable of printing crimped fibers which mimicked the fiber profile in human tendon, and has the potential in scaffold fabrication for tendon tissue engineering.