Simple synthesis of soft, tough, and cytocompatible biohybrid composites

• DOI: 10.1073/pnas.2116675119
• Publication Date: 2022-07-08T18:40:47Z
• Authors: Cameron Darkes-Bu...; Xiao Liu; Leigh Slyker; Jason Mulderrig; Wenyang Pan; Emmanuel P. Giann...; Robert F. Shepherd; Lawrence J. Bonassar; Nikolaos Bouklas
• Keywords: Collagen fibril; Matrix (chemical analysis)

Collagen is the most abundant component of mammalian extracellular matrices. As such, development materials that mimic biological and mechanical properties collagenous tissues an enduring goal biomaterials community. Despite molded 3D printed collagen hydrogel platforms, their use as tissue engineering scaffolds hindered by either low stiffness toughness or processing complexity. Here, we demonstrate stiff tough biohybrid composites combining with a zwitterionic through simple mixing. This combination led to self-assembly nanostructured fibrillar network was ionically linked surrounding matrix, leading composite microstructure reminiscent soft tissues. The addition 5–15 mg mL −1 formation fibrils increased elastic modulus system 40% compared base matrix. Most notably, fracture energy nearly 11-fold ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" overflow="scroll"> <mml:mrow> <mml:mtext>Γ</mml:mtext> <mml:mo>=</mml:mo> </mml:mrow> </mml:math> 180 J m −2 ) clearly delayed crack initiation propagation. These exhibit <mml:mi>E</mml:mi> 0.180 MJ) <mml:msup> <mml:mi>W</mml:mi> <mml:mo>*</mml:mo> </mml:msup> <mml:mo> </mml:mo> 0.617 MJ −3 approaching such articular cartilage. Maintenance structure also greatly enhanced cytocompatibility, improving cell adhesion more than 100-fold &gt;90% viability.