3D printing of biocompatible low molecular weight gels: Imbricated structures with sacrificial and persistent N-alkyl-d-galactonamides

• Published in: Journal of colloid and interface science 2022-07, Vol.617, p.156-170
• Main Authors: Andriamiseza, Faniry, Bordignon, Delphine, Payré, Bruno, Vaysse, Laurence, Fitremann, Juliette
• Format: Article
• Language: English
• Subjects: 3D printing; Additive manufacturing; Bioprinting; Biotechnology; Cell culture; Cell Culture Techniques; Chemical Sciences; Direct ink writing; Humans; Hydrogels - chemistry; Ink; Life Sciences; LMWG; Low molecular mass gel; Low molecular weight gel; Material chemistry; Molecular gel; Molecular Weight; Printing, Three-Dimensional; Self-assembled fibers; Self-assembly; Supramolecular; Tissue Engineering; Tissue Scaffolds - chemistry
• ISSN: 0021-9797; 1095-7103
• DOI: 10.1016/j.jcis.2022.02.076

[Display omitted] We have shown earlier that low molecular weight gels based on N-heptyl-d-galactonamide hydrogels can be 3D printed by solvent exchange, but they tend to dissolve in the printing bath. We wanted to explore the printing of less soluble N-alkyl-d-galactonamides with longer alkyl chains. Less soluble hydrogels could be good candidates as cell culture scaffolds. N-hexyl, N-octyl and N-nonyl-d-galactonamide solutions in dimethylsulfoxide are injected in a bath of water following patterns driven by a 2D drawing robot coupled to a z-platform. Solubilization of the gels with time has been determined and solubility of the gelators has been measured by NMR. Imbricated structures have been built with N-nonyl-d-galactonamide as a persistent ink and N-hexyl or N-heptyl-d-galactonamide as sacrificial inks. Human mesenchymal stem cells have been cultured on N-nonyl-d-galactonamide hydrogels prepared by cooling or by 3D printing. The conditions for printing well-resolved 3D patterns have been determined for the three gelators. In imbricated structures, the solubilization of N-hexyl or N-heptyl-d-galactonamide occurred after a few hours or days and gave channels. Human mesenchymal stem cells grown on N-nonyl-d-galactonamide hydrogels prepared by heating–cooling, which are stable and have a fibrillar microstructure, developed properly. 3D printed hydrogels, which microstructure is made of micrometric flakes, appeared too fragile to withstand cell growth.