Daniel Aragón-Lozano, Mariana S. Flores-Jimenez, Alejandro Garcia-Gonzalez, Yocanxóchitl Perfecto-Avalos, Fabian Rho-Mas, Ricardo García-Gamboa, Rita Q. Fuentes-Aguilar and Isaac Chairez
This study aims to develop and validate an integrated extrusion bioprinting system that produces planar and non-planar scaffolds with embedded living material (bacteria or…
Abstract
Purpose
This study aims to develop and validate an integrated extrusion bioprinting system that produces planar and non-planar scaffolds with embedded living material (bacteria or mammalian cells), overcoming the limitation of traditional extrusion bioprinting, where the material is deposited and cultured in planar layers.
Design/methodology/approach
The bioprinting device was constructed by modifying a fused deposition modelling 3D printer, adapting the extrusion holder for hydrogel-bioinks, going from an 8-bit architecture to a 32-bit one andad hoc updating the firmware, increasing the processing capacity and enabling accurate deposition of material. The device performance was assessed in hydrogel 3D planar and non-planar extrusion, considering different radius of curvature to form porous scaffolds, evaluating their ability to retain the designed curved geometry and the cell viability maintaining in bacterial and mammalian cells bioinks.
Findings
The viability (up to 99%) and growth of bacteria and mammalian cells embedded in the scaffolds was confirmed by confocal microscopy. The suggested bioprinting platform and procedure integrates an efficient strategy for producing hydrogel-based scaffolds, obtaining 98% resolution in planar deposition. For non-planar scaffolds, it was found that they are capable of maintaining the designed curvature even after being removed from the support, with an 88% of resolution.
Originality/value
It is reported a novel and advanced 3D extrusion bioprinting strategy for producing curved and complex scaffolds, preserving resolution and sterile conditions, introducing in addition a methodology for direct design and generation of a g-code with continuous and smooth paths, pioneering on the 3D bioprinting of bacterial bioinks.
Details
Keywords
Diana L. Ramírez-Gutiérrez, Enrique Cuan-Urquizo and Rita Q. Fuentes-Aguilar
Demanding applications could benefit from the mathematical parametrization of lattice structures as this could lead not only to the characterization of structure–property relation…
Abstract
Purpose
Demanding applications could benefit from the mathematical parametrization of lattice structures as this could lead not only to the characterization of structure–property relation but also facilitates the tailoring of the effective mechanical properties. This paper aims to characterize the mechanical performance of sine-based lattices. The characterization includes the results of in-plane Poisson’s ratio plates models, and the stiffness of additively manufactured lattice plates when loaded in the out-of-plane direction, with the objective of obtaining a relation with their geometrical parameters.
Design/methodology/approach
The geometrical parameter–Poisson’s ratio relationship was characterized via finite element (FE) simulations. The stiffness was also measured on additively manufactured polylactic acid lattice plates and contrasted with FE computations.
Findings
The characterization of auxetic lattice plates performed using in-plane and out-of-plane loading leads to key properties when deciding the geometry specific for applications: relative density, auxetic behavior and stiffness. Approximately 26% reduction of stiffness was observed between the square lattice and sine-based lattices of the same volume fraction.
Originality/value
Auxetic metamaterials are potential candidates for applications in biomedical engineering, smart sensors, sports and soft robotics. This paper aims to contribute to the existing gap in the study of auxetic metamaterials subjected to complex loading conditions, other than simple tension and compression, required for the mentioned applications.