Discipline: Technology and Engineering
Subcategory: Biomedical Engineering
Room: Virginia B
Janae Bradley - University of Missouri
Co-Author(s): David Grant, University of Missouri, Columbia, MO; John Brockman, University of Missouri, Columbia, MO
Introduction: Aging or severe injury to the spinal column can lead to the degradation of vital collagen fibers and proteoglycans of the intervertebral disc (IVD). Which can lead to chronic back pain, disc herniation, and disability.  Lower back pain is one of the leading causes of disability, affecting 11.9% of the population worldwide.  Due to its biocompatibility properties, collagen is utilized in tissue engineering applications as a template material in its fibrillized form. Viscoelastic collagen in its non-fibrillized form, however, displays viscous and elastic properties, which is desired to mimic the gel-like properties of the nucleus pulposus. The use of gold nanoparticles (AuNPs) adds the benefits of anti-inflammatory and anti-oxidative properties. Genipin is utilized to attach gold nanoparticles to collagen and improve collagen’s structural properties. The goal of this project was to develop, fabricate and characterize different formulations of viscoelastic collagen conjugated with gold nanoparticles to assess the feasibility as a tissue template. It is hypothesized that a unique AuNP viscoelastic (VE) material will serve as a tissue template, which will demonstrate viscoelasticity, biocompatibility, and modulate inflammation.
Materials and Methods: Type 1 bovine collagen was utilized to develop the viscoelastic collagen as the tissue scaffold. Genipin along with varying concentrations of AuNPs (20 nm and 100 nm in diameter, respectively) were utilized during the fabrication of the viscoelastic collagen scaffolds. Cysteamine was used to functionalize the NPs prior to conjugation. The following tests were used to characterize the scaffolds: Transmission Electron Microscopy (TEM) and Energy Dispersive Spectroscopy were utilized to examine the morphology of the scaffolds and to confirm the conjugation of the gold and nanoparticles; Instrumental Neutron Activation Analysis (INAA) was utilized to determine the concentration of gold nanoparticles; WST-1 cell culture assays were used to determine cytotoxicity.
Results and Discussion: STEM images and EDS data showed that the AuNPs were conjugated to the collagen scaffolds. INAA indicated an increase in the amount of gold was detected on the VE collagen samples as concentration of AuNPs increased. The WST studies demonstrated that the scaffolds that contained concentrations of AuNPs and genipin were not cytotoxic.
Conclusion: Results confirmed the presence of gold nanoparticles to the viscoelastic collagen as well as an increase in cell viability and stability. The findings from this study could lead to the development of a more efficient and cost-effective treatment for patients with disc degeneration.
 Humzah, M. D. and R. W. Soames (1988). ‘Human intervertebral disc: Structure and function.’ Anatomical Record 220(4): 337-356.
 Park, P., et al. (2004). ‘Adjacent Segment Disease after Lumbar or Lumbosacral Fusion: Review of the Literature.’ Spine 29(17): 1938-1944.
Funder Acknowledgement(s): This study was supported by the University of Missouri F21C fund.
Faculty Advisor: Sheila Grant, firstname.lastname@example.org
Role: All studies were conducted by me except for the Instrumental Neutron Activation Analysis experiment which was collaborated with and performed by Dr. John Brockman's lab at the University of Missouri.