Silylated biomolecules: Versatile components for bioinks.

Physical hydrogels prepared from natural biopolymers are the most popular components for bioinks. However, to improve the mechanical properties of the network, in particular its durability for long-lasting tissue engineering applications or its stiffness for bone/cartilage applications, covalent chemical hydrogels have to be considered. For that purpose, biorthogonal reactions are required to allow the inclusion of living cells within the bioink reservoir before the 3D printing procedure.

Design of PEGylated Three Ligands Silica Nanoparticles for Multi-Receptor Targeting.

The synthesis of silica nanoparticles (SiNPs) decorated on their surface with a range of various elements (e.g., ligands, drugs, fluorophores, vectors, etc.

Inorganic Sol-Gel Polymerization for Hydrogel Bioprinting.

An inorganic sol-gel polymerization process was used as a cross-linking reaction during three-dimensional (3D) bioprinting of cell-containing hydrogel scaffolds. Hybrid hydroxypropyl methyl cellulose (HPMC), with a controlled ratio of silylation, was prepared and isolated as a 3D-network precursor. When dissolved in a biological buffer containing human mesenchymal stem cells, it yields a bioink that can be printed during polymerization by extrusion.

Biocompatible Glycine-Assisted Catalysis of the Sol-Gel Process: Development of Cell-Embedded Hydrogels.

The sol-gel process can be used for hydrogel cross-linking, thus opening an attractive route for the design of biocompatible hydrogels under soft conditions. The sol-gel process can be catalysed at basic or acidic pH values, under neutral conditions with the addition of a nucleophile. Therefore, working around pH 7 unlocks the possibility of direct cell embedment and the preparation of bioinks.

The presence of PEG on nanoparticles presenting the c[RGDfK]- and/or ATWLPPR peptides deeply affects the RTKs-AKT-GSK3β-eNOS signaling pathway and endothelial cells survival.

Covering the surface of a nanoparticle with polyethylene glycol (PEG) is a common way to prevent non-specific interactions but how its presence impacts on the activity of targeting ligands is still poorly documented. We synthesized a set of 9 silica nanoparticles grafted with c[RGDfK]-, a peptide targeting integrin αß (cRGD) and/or with ATWLPPR, an anti-neuropilin 1 peptide (ATW). We then added various PEGs, and studied NPs binding on primary endothelial cells, the downstream activated signaling pathways and the impact on apoptosis.

Inorganic polymerization: an attractive route to biocompatible hybrid hydrogels.

As an intermediate state between liquid and solid materials, hydrogels display unique properties, opening a wide scope of applications, especially in the biomedical field. Organic hydrogels are composed of an organic network cross-linked via chemical or physical reticulation nodes. In contrast, hybrid hydrogels are defined by the coexistence of organic and inorganic moieties in water.