Development of a 3D-printable matrix using cellulose microfibrils/guar gum-based hydrogels and its post-printing antioxidant activity

A biomaterial ink suitable for three-dimensional (3D) printing was developed using cellulose microfibrils (CMFs, 1% w/v) and guar gum (1-7 g/100 mL CMFs), and the post-printing stability and antioxidant functionality of the borax-treated construct were investigated. Rheological analysis, Fourier transform infrared spectrometry, X-ray diffractometry, and scanning electron microscopy revealed the suitability of the two polymers to form an interpenetrating composite hydrogel that would facilitate printability. The produced composite hydrogel showed good structural, morphological, thermal, and textural properties. CMFs with 5% guar gum showing optimal surface properties and rheological properties were printed with the least dimensional errors at 50% infill density, 10 mm/s printing speed, 0.8 mm nozzle diameter, and 0.5 mm layer height. The treatment with borax showed good shape fidelity during 12 h storage. The treated construct also showed considerably increased mechanical properties and antioxidant activities in comparison with the untreated construct. A stable 3D construct suitable for a variety of applications could be produced using CMFs and guar gum-based ink.