Fabrication of three-dimensional scaffolds using precision extrusion deposition with an assisted cooling device

Abstract

In the field of biofabrication, tissue engineering and regenerative medicine, there are many methodologies to fabricate a building block (scaffold) which is unique to the target tissue or organ that facilitates cell growth, attachment, proliferation and/or differentiation. Currently, there are many techniques that fabricate three-dimensional scaffolds; however, there are advantages, limitations and specific tissue focuses of each fabrication technique. The focus of this initiative is to utilize an existing technique and expand the library of biomaterials which can be utilized to fabricate three-dimensional scaffolds rather than focusing on a new fabrication technique. An expanded library of biomaterials will enable the precision extrusion deposition (PED) device to construct three-dimensional scaffolds with enhanced biological, chemical and mechanical cues that will benefit tissue generation. Computer-aided motion and extrusion drive the PED to precisely fabricate micro-scaled scaffolds with biologically inspired, porosity, interconnectivity and internal and external architectures. The high printing resolution, precision and controllability of the PED allow for closer mimicry of tissues and organs. The PED expands its library of biopolymers by introducing an assisting cooling (AC) device which increases the working extrusion temperature from 120 to 250 °C. This paper investigates the PED with the integrated AC's capabilities to fabricate three-dimensional scaffolds that support cell growth, attachment and proliferation. Studies carried out in this paper utilized a biopolymer whose melting point is established to be 200 °C. This polymer was selected to illustrate the newly developed device's ability to fabricate three-dimensional scaffolds from a new library of biopolymers. Three-dimensional scaffolds fabricated with the integrated AC device should illustrate structural integrity and ability to support cell attachment and proliferation.

Fabrication of Biological Microfluidics Using a Digital Microfabrication System

“…A fluorometric indicator (Alamar Blue, Serotec) of cell metabolic activity was utilized to determine the cell proliferation within the channels of both treated and untreated chips (closed and open) [30][31][32]. The open cell laden chips were removed from the petri dishes, washed twice with 1 x phosphate buffered saline (PBS), placed into a new dish where 10% (v/v) Alamar blue was added and incubated for 4h.…”

Progress of key strategies in development of electrospun scaffolds: bone tissue

“…The shape of the unit cells depends on the fabrication technique. For electrospun fibrous scaffolds, the unit cell geometry of a 3D scaffold is defined by the arrangement of fibers, which in turn controls the interconnecting porosity in the scaffold [2,37,48]. However, controlling the uniformity in 3D structure generation via electrospinning is very difficult without a deep involvement of the whole architecture of the scaffold, including the unit cell geometry and fiber orientation.…”

Bioprinting for cancer research

“…The interest in bioprinting has significantly grown within the scientific and medical communities due to several key advantages over previously accepted fabrication methods such as photolithography, soft lithography, and microstamping. These advantages include the ability to create geometrically complex scaffolds containing viable cells [18,19,21], efficiency, low cost [22], high throughput [23], precise reproducibility [18], and limited need for specialized training. High-throughput fabrication of 3D structures is currently limited with traditional microfabrication techniques that generate 2D building blocks and rely on layer-by-layer assembly to form 3D structures [24][25][26][27][28][29][30][31][32].…”