DOI

10.17077/etd.1kygy0aj

Document Type

Thesis

Date of Degree

Summer 2016

Degree Name

MS (Master of Science)

Degree In

Biomedical Engineering

First Advisor

M. L. Suresh Raghavan

First Committee Member

Joseph Turek

Second Committee Member

Nicole M. Grosland

Abstract

Novel biomaterials provide a spectrum of possibilities. They can be engineered in different forms to understand how they would perform as different bioprosthetic conduits. Bacterial cellulose membranes may be suitable candidates as prosthetic valve leaflets in valve replacement surgeries due to their functional properties (hemodynamics, resistant to thrombosis). Biomaterials used for most bioprosthetic heart valves are cut, trimmed and sutured. A major challenge for the bi-leaflet configuration is that the cutting and suturing of biopolymers fabricated as sheets into a cylindrical form increases failure risk due to greater number of suture points and irregular coaptation. The objective was to culture the bacterial cellulose membrane as a continuous cylindrical construct and evaluate its mechanical properties. Various design features of the fabrication process such as culturing media and the hollow carrier-mandrel characteristics were evaluated. A comparative study of how bacterial cellulose grows on different hollow carrier membranes was conducted and thin smooth surface silicone tubes fabricated in the lab were found to be most suitable. A bioreactor for culturing cylindrical bacterial cellulose tubes on the outer surface of the hollow carrier was designed and fabricated. The mechanical properties of the fabricated tubes, specifically, their tensile strength, flexure, suture retention and tear resistance were characterized. Mechanical characterization studies showed the cylindrical bacterial cellulose tubes to be anisotropic, with preferential properties in the longitudinal (axial) direction of the tube. Preliminary results show that cylindrical bacterial cellulose tubes can be a promising candidate for use in prosthetic valve conduits.

Keywords

Bacterial Cellulose, Biomedical Engineering, Cylindrical Bacterial Cellulose, Pediatric pulmonary bioprosthetic heart valve, Pulmonary bioprosthesis, Transcatheter Heart Valves

Pages

xi, 39 pages

Bibliography

Includes bibliographical references (pages 37-39).

Copyright

Copyright © 2016 Srivats Sarathy

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