# Synthesis and Characterization of a Marine Collagen–Chitosan/HA–SiO2-Based Bioink

## TL;DR

This paper describes the creation and testing of a new bioink using marine collagen, chitosan, and silica-doped hydroxyapatite for 3D bioprinting.

## Contribution

The novel contribution is the development and characterization of a marine collagen–chitosan/HA–SiO2-based bioink suitable for extrusion-based bioprinting.

## Key findings

- The bioink showed elastic dominance and shear-thinning behavior suitable for pneumatic extrusion.
- SEM analysis revealed an interconnected porous microstructure.
- Filament continuity was limited, indicating preliminary printability and a narrow operating window.

## Abstract

In this work, we report the synthesis and evaluation of a bioink based on marine collagen, chitosan, and silica-doped hydroxyapatite (HA–SiO2) for extrusion-based 3D bioprinting. FTIR spectroscopy confirmed amide (I–III) and phosphate/siloxane signals, TGA showed initial dehydration and degradation stages compatible with the process’s thermal handling, and SEM revealed an interconnected porous microstructure. Rheologically, the ink exhibited elastic dominance (G′ > G″) within the linear range and pseudoplastic, shear-thinning behavior—consistent with pneumatic extrusion. Process evaluation on a BIO X printer (14 G nozzle, low print speeds, moderate pressure, cartridge at 37 °C to 45 °C, and a cooled build platform) enabled deposition of strands with local shape retention. However, filament continuity was limited and line width varied, indicating only preliminary printability and a narrow operating window. Overall, physicochemical, microstructural, and rheological evidence supports the formulation’s viability as a starting point for scaffold fabrication.