Three-dimensional printing of alginate-gelatin-agar scaffolds using free-form motor assisted microsyringe extrusion system

In current study, three-dimensional scaffolds of alginate-gelatin-agar were fabricated using free-form motor assisted microsyringe (MAM) extrusion system. Briefly, a hydrogel solution comprised of 18 wt% sodium alginate, 4 wt% gelatin, and 12 wt% agar was prepared by dissolving all components in sterile deionized water. Cubic scaffold with dimensions 9 × 9 × 9 mm3 were printed in a layer-by-layer fashion and sintered. Fourier transform infrared (FTIR) spectroscopy confirmed the chemical structure of scaffold. Field emission scanning electron microscopy (FE-SEM) analysis showed the fabrication of highly porous scaffolds with patterned structure and uniformly distributed holes at the surface. The dynamic contact angle measurement of alginate-gelatin-agar scaffold demonstrated its hydrophilic nature. The maximum tensile strength at breaking point, Young’s modulus, and elongation strain of scaffold were found to be 31.21 MPa, 0.83 GPa, and 2.51%, respectively. The scaffold supported the adhesion and growth of Hela cells. The interaction of scaffold with Escherichia coli and Saccharomyces cerevisiae as determined by the cell viability analysis through Alamar Blue assay demonstrated improved growth of microbial cells. This study can provide new dimension to the current bioprinting technology to develop patterned structure and microbes based micro/nano robots and devices.