Computational and Experimental Characterization of Aligned Collagen across Varied Crosslinking Degrees

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Materials Science

Background:

• Collagen scaffolds are crucial in tissue engineering, with fiber alignment and crosslinking significantly influencing cell activity, stability, and mechanical properties.
• Understanding the impact of microarchitecture and crosslinking is vital for fabricating collagen scaffolds with tailored mechanical performance.

Purpose of the Study:

• To quantify the effects of collagen fiber alignment and crosslinking degree on the mechanical properties of collagen threads.
• To establish a combined experimental and computational approach for predicting scaffold mechanical behavior.

Main Methods:

• Fabrication of electrochemically aligned collagen (ELAC) and randomly distributed collagen threads.
• Uniaxial mechanical testing and finite element method (FEM) analysis.
• Varying genipin concentrations (0.1% or 2%) and crosslinking durations (1, 4, 24 h) to control crosslinking degrees.

Main Results:

• Aligned collagen fibers and increased crosslinking significantly enhance Young's modulus.
• Aligned collagen increased Young's modulus by 112.7% compared to random collagen at a 25% crosslinking degree.
• Increasing genipin concentration from 0.1% to 2% (4 h) boosted ELAC Young's modulus by 90.3%.

Conclusions:

• Fiber alignment and crosslinking degree are critical, controllable parameters for collagen scaffold mechanical properties.
• Verified computational models can predict mechanical properties, aiding in controlled fabrication.
• This systematic approach enables precise fabrication of collagen threads for advanced tissue engineering.