Hidrogéis de carboximetilcelulose/amido fabricados por impressão 3D para uso como substratos para cultivo celular

Abstract

The use of hydrogels as biomaterials has significantly grown in recent decades, and with the aid of additive manufacturing processes, new materials with complex shapes and geometries have been produced for use as scaffolds. As a contribution to this research field, a bioink of carboxymethylcellulose (CMC) and starch (St) was formulated and used for 3D printing of hydrogels, which will be tested as scaffolds for cell culture. The CMC/St bioink, supplemented with 15% (w/w) citric acid (crosslinking agent), showed favorable rheological properties, ensuring a good printing capability. Scanning electron microscopy images revealed that the printed hydrogels have a dual-porous structure, with relatively large pores (336.6 ± 32.5 μm) and uniformly distributed micropores of medium size (60.3 ± 18.9 μm). Platelet-rich plasma (PRP) was adsorbed on the hydrogels as a strategy to enhance their biological activity. The presence of PRP on the hydrogel surface resulted in changes in porosity and thermal properties, indicating its incorporation. Alongside characterization analyses, stability tests confirmed the crosslinking of the CMC/St hydrogels and demonstrated their high stability in water, cell culture medium, and phosphate-buffered saline (PBS) at pH 7.4. Mechanical analyses revealed that PRP did not significantly alter the material's stiffness, while CMC/St hydrogels swollen in PBS showed a 72% increase in elastic modulus compared to PRP-containing hydrogels (CMC/St PRP). Finally, the CMC/St hydrogels exhibited a high swelling rate (kinetics), reaching a maximum of 136% in PBS in just 5 minutes, which is attributed to the hydrophilic nature of the matrix and its porous morphology. All these features are appealing for potential future testing of CMC/St hydrogels as scaffolds for tissue engineering and regenerative medicine applications.