Thermo-/photo-responsive Bioink for Enhanced Printability in Extrusion-Based Bioprinting

초록

Extrusion-based bioprinting has demonstrated great potential for fabricating constructs, especially for three-dimensional (3D) cell culture. However, the number of bioink candidates suitable for extrusion-based bioprinting techniques is minimal, as they meet the opposing requirements for printability with specific rheological properties and for biochemical cues with a favorable microenvironment. In this study, a blend of silk fibroin (SF) and iota-carrageenan (CG) was developed as a cell-desirable and printable material. The SF/CG ink exhibited appropriate viscosity and shear-thinning behavior, along with the rapid sol-gel transition characteristic of CG. Photo-crosslinking of SF was employed to enhance the printability, yielding 3D constructs with a Pr value close to 1 and improved the structural integrity within seconds. The printed scaffolds exhibited a Young's modulus of approximately 250 kPa, rendering them suitable for supporting keratinocyte and myoblast cell culture. Furthermore, high cell adhesion and viability (> 98%) of the encapsulated cells demonstrated the significant potential of this SF/CG-based 3D cellular scaffold for applications in skin and muscle tissues, which can be easily engineered with an extrusion-based bioprinter.