3D printable hydrogel filament with functionalizable moiety for in-situ flow-based sensor

Understanding microorganisms is a worthy work to gather various biological information that can directly affect human beings. However, most information is detected or measured at ex-situ conditions. In this work, we attempted to fabricate a 3D printable hydrogel-based in-situ detection system. We designed the hydrogel containing azide functionalized polyethylenglycole methacrylate (PEGMA) and fabricated the hydrogel as a 3D structure to prepare flow type detector using a 3D printer. To use hydrogel as a 3D printer filament, we enhanced viscosity via the pre-crosslinking process and added bentonite with Polyethylene glycol diacrylate (PEGDA) crosslinker with a certain proportion. Prepared hydrogel 3D structure could cultivate E.coli in a liquid culture medium. The hydrogel 3D structure has an azide group which is a useful tool to introduce additional chemical functionality via azide–alkyne click reaction. Using this process, we introduced alkyne functionalized 4-(2-pyridylazo) resorcinol (PAR). The PAR clicked hydrogel can be used as flow based sensor platform to detect i.e. various metal ions including Cu, Al, and Co ions in media. Graphical Abstract Schematic diagram of final concept of azide-functionalized hydrogel-based in-situ detector