Available at: https://digitalcommons.calpoly.edu/theses/3020
Date of Award
6-2025
Degree Name
MS in Biomedical Engineering
Department/Program
Biomedical Engineering
College
College of Engineering
Advisor
Kristen O'Halloran Cardinal
Advisor Department
Biomedical Engineering
Advisor College
College of Engineering
Abstract
Novel Electrospinning Techniques for Fabricating Scaffolds to Model Intracranial
Atherosclerotic Disease in Tissue Engineered Blood Vessel Mimics
Isaac “Squeaky” Buentipo
Dr. Kristen Cardinal’s Tissue Engineering Lab at California Polytechnic State University specializes in fabricating customized vascular models, known as Blood Vessel Mimics (BVMs), for medical device testing. BVMs are simplified in vitro vascular models designed to bridge the gap between bench testing and in vivo evaluation of intravascular medical devices. BVMs are produced by combining a polymer scaffold with human vascular cells. Through novel scaffold fabrication techniques, such as silicone injection molding, silicone dip casting and electrospinning, the capabilities of the BVM model have evolved to model tortuous vessels and vascular pathologies, including aneurysms. However, the current modeling capabilities do not extend to luminally occluded vascular pathologies, such as intracranial atherosclerotic disease (ICAD). Therefore, the goal of this thesis was to develop and fabricate an electrospun fibrous polymer scaffold with luminal occlusion, suitable for translation into a blood vessel mimic.
The first aim of this thesis was to investigate the feasibility of the methods used for fabricating and characterizing fibrous polymer scaffolds with internal geometries, using a modified collection mandrel. Electrospinning parameters for optimal internal geometry generation on the modified mandrel were identified and implemented. Although scaffolds were successfully fabricated, the occlusion levels were insufficient to be clinically relevant. This limitation led to the second aim, which focused on investigating novel electrospinning approaches to create fibrous polymer scaffolds with clinically relevant lesions. By exploring mandrel additions and mandrel alterations, the newly fabricated barbell mandrel emerged as the optimal method for fabricating customizable occluded scaffolds. Using this technique, scaffolds were generated with 50% and 70% luminal occlusion and lesion lengths ranging from 0.5 cm to 3 cm. The third aim of this thesis evaluated the preliminary efficacy of the generated occluded scaffolds as BVMs through an acute vessel cultivation study, assessing cell deposition across the scaffold lumen. The results showed consistent cell deposition across the generated vessels. Further work is needed to generate occluded vessels over longer cultivation periods to fully evaluate their utility as disease models for medical device testing. In summary, this thesis developed and implemented methods for electrospinning luminally occluded fibrous polymer scaffolds and demonstrated their preliminary application in creating BVMs, laying the groundwork for future advancement of occluded vessel modeling within Kristen Cardinal’s Tissue Engineering Lab.