Low-Concentration Gelatin Methacryloyl Hydrogel with Tunable 3D Extrusion Printability and Cytocompatibility:...

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Bioprinting Technology

Background:

• 3D bioprinting of hydrogels lacks comprehensive understanding of process-science, buildability, and biophysical property correlations.
• Quantitative analysis of 3D extrusion bioprinting for scaffolds is not widely reported.
• Developing multifunctional bioinks with tunable properties is crucial for clinical applications.

Purpose of the Study:

• To investigate the influence of methacrylated carboxymethyl cellulose (mCMC), nanohydroxyapatite (nHAp), and poly(ethylene glycol)diacrylate (PEGDA) on gelatin methacryloyl (GelMA) based bioinks.
• To establish correlations between bioink formulation, viscoelastic properties, printability, and large-scale scaffold buildability.
• To evaluate the cytocompatibility and potential for bone and cartilage tissue regeneration using these bioinks.

Main Methods:

• Utilized GelMA as a baseline matrix, incorporating mCMC, nHAp, and PEGDA to create multifunctional bioinks.
• Performed extensive experiments and quantitative analysis to assess biophysical properties, printability, and cellular functionality.
• Fabricated 15 mm edge cube scaffolds using 3D extrusion bioprinting and evaluated their structural stability.

Main Results:

• Incorporation of PEGDA significantly improved compressive modulus (∼40-fold), reduced swelling ratio (∼2-fold), and decreased degradation rates (∼30-fold) compared to pristine GelMA.
• Established correlations between microstructural pore architecture, biophysical properties, and cytocompatibility of the developed bioinks.
• Demonstrated successful growth and differentiation of human mesenchymal stem cells (hMSCs) into bone and cartilage matrix on 2D substrates and within 3D scaffolds.

Conclusions:

• The developed photopolymerizable bioinks offer a versatile platform for 3D bioprinting of multifunctional scaffolds with shape fidelity.
• Quantitative analysis is essential for establishing process-microstructure-property correlations in bioink development.
• This work represents a significant advancement in creating advanced bioinks for bone and cartilage tissue engineering applications.