Charge-Neutral Microgels for 3D Cell Culture and Printing

Improves permeability, allowing for easier perfusion than previous compositions

These charge-neutral microgels allow for 3D cell culture and printing. Bioprinting, or placement of biological samples into 3D support media, models cellular morphology, heterogeneity, and genetic profiles in a more accurate and reproducible fashion than traditional 2D cultures. Available 3D cell culture strategies involve the seeding and adhesion of cells into polymer scaffolds with subsequent perfusion of growth media. However, these systems present several limitations, such as limited cell migration, lack of time-effectiveness and optical access for microscopy, and polymer scaffolds restricting the cell environment. Additionally, cell viability is limited to a few days due to the accumulation of cellular waste, leading to localized cytotoxic environments and cell death. It is necessary to devise 3D growth media that allows for improved perfusion.

Researchers at the University of Florida have developed smooth, spherical charge-neutral microgels suitable for 3D cell culture and printing. They can also be used in perfusion bioreactors. The microgels’ spherical shapes enable easier perfusion of materials and make the microgel more absorbent than currently available options.

Application

Microgel-based medium for 3D cell culture and printing, allowing for easier perfusion of materials than currently available formulations

Advantages

• Microgel particles constitute nearly perfect spheres with well-defined pore spaces between microgels, making them 10,000 times more permeable
• Well-defined pore spaces between microgels, enabling easier perfusion
• Polymers are charge neutral, making swelling and packing of microgels insensitive to changes in solvent composition

Technology

These microgels consist of charge-neutral particles, enabling 3D cell culture and printing. The development of the microgels involves emulsion polymerization, more specifically, an inverse emulsion reaction, resulting in spherical microparticles comprising cross-linked polymers with superior properties for 3D culture. The microgels are derived from monomers, including poly (ethylene glycol) methyl ether acrylate (PEGa), poly(ethylene glycol) diacrylate (PEGda), or acrylamides, N-alkylacrylamides, N,N-dialkylacrylamides, and (meth)acrylates. Packed spherical microgels create well-defined and large pores spaces, improving permeability by a factor of 10,000 compared to currently available formulations, and allowing for easier perfusion of materials.