Type
Text
Type
Dissertation
Advisor
Sitharaman, Balaji | Qin, Yi-Xian | Judex, Stefan | Meng, Yizhi.
Date
2015-12-01
Keywords
Biomedical engineering | Biomaterials, Carbon nanotubes, Scaffolds, Stem cell expansion, Tissue Engineeirng, Toxicity
Department
Department of Biomedical Engineering.
Language
en_US
Source
This work is sponsored by the Stony Brook University Graduate School in compliance with the requirements for completion of degree.
Identifier
http://hdl.handle.net/11401/76993
Publisher
The Graduate School, Stony Brook University: Stony Brook, NY.
Format
application/pdf
Abstract
Assembly of carbon nanomaterials into three-dimensional (3D) architectures is necessary to harness their unique physiochemical properties for tissue engineering and regenerative medicine applications. In this dissertation, fabrication and characterization of 3D chemically crosslinked macro-sized (5-8 mm height and 4-6 mm diameter) porous carbon nanotube (CNT) scaffolds, their in vitro cytocompatibility and interactions with human mesenchymal stem cells (hMSCs) are reported. Single- or multi-walled carbon nanotubes (SWCNTs or MWCNTs) scaffolds were fabricated using a novel radical initiated thermal crosslinking and annealing method using SWCNTs or MWCNTs as nanoscale building blocks. The scaffolds possess macroscale interconnected pores, robust structural integrity, stability, and electrical conductivity. Varying the amount of radical initiator can control the porosity of the 3D structure; thereby allowing the design of porous scaffolds tailored towards specific biomedical applications. MC3T3 pre-osteoblast cells and human adipose-derived stem cells (ADSCs) on MWCNT and SWCNT scaffolds (>80% porosity) showed good cell viability comparable to poly(lactic-co-glycolic) acid (PLGA) scaffolds. Confocal live cell and immunofluorescence imaging showed that MC3T3 pre-osteoblasts and ADSCs were metabolically active and could attach, proliferate and infiltrate MWCNT and SWCNT scaffolds. SEM imaging corroborated cell attachment and spreading and suggested that cell morphology is governed by scaffold surface roughness. MC3T3 cells were elongated on scaffolds with high surface roughness (MWCNTs) and rounded on scaffolds with low surface roughness (SWCNTs). The surface roughness of scaffolds may be exploited to control cellular morphology, and in turn govern cell fate. The plasticity of ADSCs was assessed according to International Society for Cellular Therapy guidelines after long-term culture (15 and 30 days) on CNT scaffolds. The plasticity of ADSCs is maintained after 15 days of culture on 3D SWCNT and MWCNT scaffolds (ADSCs were positive for CD105, CD73 and CD90, and negative for CD45, CD34, CD14 and CD19). ADSCs harvested from 3D MWCNT and SWCNT scaffolds after 30 days show in-vitro expansion and tri-lineage differentiation towards osteoblasts, adipocytes and chondrocytes indicating that the scaffolds do not affect differentiation capabilities of the ADSCs. These results show that 3D, macroscopic, porous MWCNT and SWCNT scaffolds with tunable porosities are cytocompatible; they can be used for the expansion and maintenance of human ADSCs and as multifunctional scaffolds for tissue engineering applications. | 178 pages
Recommended Citation
Lalwani, Gaurav, "Three-Dimensional Macroporous All-Carbon Scaffolds For Tissue Engineering Applications" (2015). Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions). 2857.
https://commons.library.stonybrook.edu/stony-brook-theses-and-dissertations-collection/2857