Design of 3-D Bioinks, Printing Hardware, and Printable Devices.
Patient-specific treatments are of paramount importance. Clinicians and biomedical
engineers have long desired to deliver strategies enabling on-demand fabrication of
customized tissue scaffolds and implant geometries. The first international workshop on
the subject defined bioplotting or bioprinting as the use of material transfer processes
for patterning and assembling biologically ... read morerelevant materials-molecules, cells, tissues,
and biodegradable biomaterials-with a prescribed organization to accomplish one or more
biological functions. The ability to design tailored implant and scaffold geometries
using three-dimensional patient scans and computer-aided design currently exist.
However, patient-specific designs require the development of accurate high-resolution
fabrication techniques. The novelty of this work is the strategy employed to cure
structurally robust 3-D bioink prints. Current additive bio-printers use curing
mechanisms which are biologically deleterious. In contrast, cell-plotters are less
damaging but produce prints which lack mechanical or cohesive strength. This approach is
able to produce mechanically robust prints without harmful or damaging curing
mechanisms. We hypothesize that the unique stabilizing properties and self-organizing
mechanism of aqueous silk protein, enhanced with non-toxic additives, can be exploited
to enable nonthermoplastic fused filament fabrication of resorbable biopolymer scaffolds
and medical devices via programmed three-dimensional deposition. This thesis details the
complete design and development of self-curing bioinks and a robotic deposition system
and programming for the purpose of 2-D and 3-D rapid prototyping. Here we demonstrate
preliminary work towards print precision and modulation, replication of CAD geometry,
and high slice number 3-D prints which demonstrate macroscale geometry and structural
strength. Successful application of this bioprinter and strategy were achieved as work
in the areas of bioprinting, implant fabrication, and
Thesis (Ph.D.)--Tufts University, 2015.
Submitted to the Dept. of Biomedical Engineering.
Advisor: David Kaplan.
Committee: Fiorenzo Omenetto, Barry Trimmer, and Samuel Lin.
Keyword: Biomedical engineering.read less