Emily Morra (ESR 6)
I received my Bachelor of Science in Biomedical Engineering with a minor in Materials Science from Worcester Polytechnic Institute in May of 2019. My studies were focused biomaterials and tissue engineering and I completed coursework in medical device design and material processing. In my final year, I developed an in vitro model of skeletal muscle regeneration for implantable fibrin microthreads as my Major Qualifying Project. During my undergraduate studies, I also spent time in industry working with bioresorbable suture and surgical mesh, as well as performing wear testing of hip and knee implants.
The combined academic-industrial approach is an extremely effective way to learn, and that’s what drew me to the BioImplant ITN. Focused research with an industrial partner promotes practical application of research with critical feedback for learning. BioImplant provides a unique opportunity to become involved in industry while completing my PhD. In the future, I would like to become involved with research and development of biomaterials in the medical device industry, with a focus on new product development.
Sterilization of biomaterials is a critical prerequisite for their successful clinical application. Bioresorbable polymers present a unique set of challenges for sterilization; in addition to being moisture and temperature sensitive, a decrease in molecular weight or change in structure affects device performance. Existing standard sterilization techniques have limitations that can negatively affect material properties. Consequently, there is a need to quantify the influence of sterilization on the mechanical and degradation properties of bioresorbable polymers.
Existing bioresorbable stents have inferior mechanical properties when compared to metallic stents. There is also a need for a better match between the stent’s degradation profile and the biological remodelling process. E-beam irradiation provides an opportunity to create localized modifications to mechanical properties and degradation profile with a beneficial effect on bioresorbable stent performance.
Project work will be divided into three phases:
Phase 1: Conduct a parametric study of different sterilization techniques and quantify the influence of sterilization on the mechanical performance of PLLA.
Phase 2: Evaluate electron beam shielding patterns on two-dimensional, biaxial stretched sheets for localized material modifications. Obtain baseline properties and properties after accelerated degradation. Investigate both chain scission and crosslinking.
Phase 3: Test shielding patterns on three-dimensional, stent-representative geometries and conduct feasibility studies relating to drug release behaviour and in vitro biocompatibility.