3D Bioplotter Research Papers

Displaying all papers by R. A. Shirwaiker (8 results)

Label free process monitoring of 3D bioprinted engineered constructs via dielectric impedance spectroscopy

Biofabrication 2018 Volume 10, Article 035012

Biofabrication processes can affect biological quality attributes of encapsulated cells within constructs. Currently, assessment of the fabricated constructs is performed offline by subjecting the constructs to destructive assays that require staining and sectioning. This drawback limits the translation of biofabrication processes to industrial practice. In this work, we investigate the dielectric response of viable cells encapsulated in bioprinted 3D hydrogel constructs to an applied alternating electric field as a label-free non-destructive monitoring approach. The relationship between β-dispersion parameters (permittivity change—Δε, Cole–Cole slope factor—α, critical polarization frequency—f c ) over the frequency spectrum and critical cellular quality attributes are investigated. Results…

Fabrication and Evaluation of Electrospun, 3D-Bioplotted, and Combination of Electrospun/3D-Bioplotted Scaffolds for Tissue Engineering Applications

BioMed Research International 2017 Volume 2017, Article ID 6956794

Electrospun scaffolds provide a dense framework of nanofibers with pore sizes and fiber diameters that closely resemble the architecture of native extracellular matrix. However, it generates limited three-dimensional structures of relevant physiological thicknesses. 3D printing allows digitally controlled fabrication of three-dimensional single/multimaterial constructs with precisely ordered fiber and pore architecture in a single build. However, this approach generally lacks the ability to achieve submicron resolution features to mimic native tissue. The goal of this study was to fabricate and evaluate 3D printed, electrospun, and combination of 3D printed/electrospun scaffolds to mimic the native architecture of heterogeneous tissue. We assessed their…

Effects of 3D-bioplotted polycaprolactone scaffold geometry on human adipose-derived stem cells viability and proliferation

Rapid Prototyping Journal 2017 Volume 23, Issue 3, Pages 534-542

Purpose This study investigates the effect of 3D-bioplotted polycaprolactone (PCL) scaffold geometry on the biological and mechanical characteristics of human adipose-derived stem cell (hASC) seeded constructs. Design/methodology/approach Four 3D-bioplotted scaffold disc designs (Ø14.5 x 2 mm) with two levels of strand-pore feature sizes and two strand laydown patterns (0°/90° or 0°/120°/240°) were evaluated for hASC viability, proliferation, and construct compressive stiffness after 14 days of in vitro cell culture. Findings Scaffolds with the highest porosity (smaller strand-pore size in 0°/120°/240°) yielded the highest hASC proliferation and viability. Further testing of this design in a 6 mm thick configuration showed that…

In vitro characterization of design and compressive properties of 3D-biofabricated/decellularized hybrid grafts for tracheal tissue engineering

Journal of the Mechanical Behavior of Biomedical Materials 2016 Volume 59, Pages 572–585

Infection or damage to the trachea, a thin walled and cartilage reinforced conduit that connects the pharynx and larynx to the lungs, leads to serious respiratory medical conditions which can often prove fatal. Current clinical strategies for complex tracheal reconstruction are of limited availability and efficacy, but tissue engineering and regenerative medicine approaches may provide viable alternatives. In this study, we have developed a new “hybrid graft” approach that utilizes decellularized tracheal tissue along with a resorbable polymer scaffold, and holds promise for potential clinical applications. First, we evaluated the effect of our decellularization process on the compression properties of…

3D-Bioprinting of Polylactic Acid (PLA) Nanofibers-Alginate Hydrogel Bioink Containing Human Adipose-Derived Stem Cells

ACS Biomaterials Science and Engineering 2016 Volume 2, Issue 10, Pages 1732–1742

Bioinks play a central role in 3D-bioprinting by providing the supporting environment within which encapsulated cells can endure the stresses encountered during the digitally-driven fabrication process, and continue to mature, proliferate, and eventually form extracellular matrix (ECM). In order to be most effective, it is important that bioprinted constructs recapitulate the native tissue milieu as closely as possible. As such, musculoskeletal soft tissue constructs can benefit from bioinks that mimic their nanofibrous matrix constitution, which is also critical to their function. This study focuses on the development and proof-of-concept assessment of a fibrous bioink composed of alginate hydrogel, polylactic acid…

Characterization of Material–Process–Structure Interactions in the 3D Bioplotting of Polycaprolactone

3D Printing and Additive Manufacturing 2015 Volume 2, Issue 1, Pages 20-31

Three-dimensional (3D) bioplotting is a melt-extrusion-based additive manufacturing process used to fabricate 3D scaffolds for tissue engineering applications. This study investigates the relationship between material rheology, process parameters, and scaffold characteristics during 3D bioplotting of polycaprolactone (PCL). The effects of two process parameters, extrusion temperature and nozzle diameter, on resultant scaffold structure and compression strength were studied using design of experiments. PCL scaffolds designed for a 24-well culture plate (Ø 14 mm × 2 mm) were bioplotted in a 0°/90° laydown pattern at three levels of extrusion temperature (80°C, 90°C, and 100°C) and two levels of nozzle inner diameter (0.3 and 0.4 mm) at…

PCL

Alginate Microspheroid Encapsulation and Delivery of MG-63 Cells Into Polycaprolactone Scaffolds: A New Biofabrication Approach for Tissue Engineering Constructs

Journal of Nanotechnology in Engineering and Medicine 2015 Volume 6, Issue 2, 021003

Scaffolds play an important role in tissue engineering by providing structural framework and a surface for cells to attach, proliferate, and secrete extracellular matrix (ECM). In order to enable efficient tissue formation, delivering sufficient cells into the scaffold three-dimensional (3D) matrix using traditional static and dynamic seeding methods continues to be a critical challenge. In this study, we investigate a new cell delivery approach utilizing deposition of hydrogel-cell encapsulated microspheroids into polycaprolactone (PCL) scaffolds to improve the seeding efficiency. Three-dimensional-bioplotted PCL constructs (0 deg/90 deg lay down, 284 ± 6 μm strand width, and 555 ± 8 μm strand separation) inoculated with MG-63 model bone cells encapsulated within…

Biocompatibility analysis of an electrically-activated silver-based antibacterial surface system for medical device applications

Journal of Materials Science: Materials in Medicine 2013 Volume 24, Issue 3, Pages 755-760

The costs associated with the treatment of medical device and surgical site infections are a major cause of concern in the global healthcare system. To prevent transmission of such infections, a prophylactic surface system that provides protracted release of antibacterial silver ions using low intensity direct electric current (LIDC; 28 μA system current at 6 V) activation has been recently developed. To ensure the safety for future in vivo studies and potential clinical applications, this study assessed the biocompatibility of the LIDC-activated interdigitated silver electrodes-based surface system; in vitro toxicity to human epidermal keratinocytes, human dermal fibroblasts, and normal human…