A Thermogelling Supramolecular Hydrogel with Sponge-Like Morphology as a Cytocompatible Bioink

Abstract

Biocompatible polymers that form thermoreversible supramolecular hydrogels have gained great interest in biomaterials research and tissue engineering. When favorable rheological properties are achieved at the same time, they are particularly promising candidates as material that allow for the printing of cells, so-called bioinks. We synthesized a novel thermogelling block copolymer and investigated the rheological properties of its aqueous solution by viscosimetry and rheology. The polymers undergo thermogelation between room temperature and body temperature, form transparent hydrogels of surprisingly high strength (G' > 1000 Pa) and show rapid and complete shear recovery after stress. Small angle neutron scattering suggests an unusual bicontinuous sponge-like gel network. Excellent cytocompatibility was demonstrated with NIH 3T3 fibroblasts, which were incorporated and bioplotted into predefined 3D hydrogel structures without significant loss of viability. The developed materials fulfill all criteria for future use as bioink for biofabrication.

Poly(2‐oxazoline) Hydrogels: State‐of‐the‐Art and Emerging Applications

“…Luxenhofer and co‐workers have recently reported a “biocompatible ink” from a triblock copolymer with a poly(2‐ n ‐propyl‐2‐oxazoline) middle block and PMeOx outer blocks, described earlier in Section . This polymer has temperature gelling properties, which was serendipitously discovered when freezing a sample for lyophilization.…”

“…Luxenhofer and co‐workers have also used MeOx as a monomer to prepare water‐soluble PAOx to encapsulate cells for biofabrication (discussed more in Section ). Rather than using a chemically cross‐linking system, they found that CROP of 2‐ n ‐propyl‐2‐oxazine using methyl triflate (MeOTf) as the initiator followed by addition of a PMeOx block to the living system resulted in polymers that would thermally gel around 20–40 °C, depending on composition.…”

Session 5: Young Scientist Forum

“…[1] The first investigations using nanoparticles of PMOs have also appeared. [2][3][4] In general, such nanoparticle systems are able to release only a single active agent, although in many cases it would be advantageous to deliver a combination of different drugs, possibly sequentially in time. For example, when implantassociated drug release is concerned, delivery of an anti-inflammatory/antibacterial drug followed by an active agent to promote healing would be beneficial.…”

“…[3] In the last decades, they have been intensely investigated especially as thermoresponsive materials [4] and for biomedical applications. [5] More recently, polypeptoid based hydrogels were reported.…”

“…These are promising materials for biomedical applications such as drug delivery systems. [3][4][5] The produced hydrogels will be used as wound patches for infected or chronic infected wounds. Therefore, so called photosensitizers shall be incorporated in the hydrogels.…”