Introduction of an Ambient 3D-Printable Hydrogel Ink to Fabricate an Enzyme-Immobilized Platform with Tunable Geometry for Heterogeneous Biocatalysis.

An enzyme-immobilized platform for biocatalysis was developed through 3D printing of a hydrogel ink comprising dimethacrylate-functionalized Pluronic F127 (F127-DMA) and sodium alginate (Alg) with laccase that can be done at ambient temperature, followed by UV-induced cross-linking. Laccase is an enzyme that can degrade azo dyes and various toxic organic pollutants. The fiber diameter, pore distance, and surface-to-volume ratio of the laccase-immobilized and 3D-printed hydrogel constructs were varied to determine their effects on the catalytic activity of the immobilized enzyme. Among the three geometrical designs investigated, the 3D-printed hydrogel constructs with flower-like geometry exhibited better catalytic performance than those with cubic and cylindrical geometries. Once tested against Orange II degradation in a flow-based format, they can be reused for up to four cycles. This research demonstrates that the developed hydrogel ink can be used to fabricate other enzyme-based catalytic platforms that can potentially increase their industrial usage in the future.