Measuring Injection Forces of Shear-Thinning Hydrogel with Integrated Microgels

Student: Shannon Grassi

Mentors: Dr. Sarah Stabenfeldt – SBHSE
Dr. Mehdi Nikkhah – SBHSE
Dr. Julianne Holloway – SEMTE

YouTube Link: View the video link below before joining the zoom meeting

Zoom link: https://asu.zoom.us/j/83703528558

Zoom meeting time: 10am - noon

Abstract

Localized injection of biomedical hydrogels has become a growing field of study for cell transplantation applications. Specifically, hydrogel dynamics and their tunable characteristics have shown promise in improved delivery of cells, growth factors, and other molecules that may aid in retention and therapeutic effects. Guest-host hydrogels have emerged as promising cell delivery carriers as they increase the survival rates of cells post injection. However, the injection force of the injectable system impacts cell survival rates. Therefore, this project focuses on the design and development of a force measurement system via a compression load cell and syringe pump. This system will be used to determine the changes in shear force required to break the guest-host network of shear-thinning hydrogels with varying concentrations of added norbornene hyaluronic acid (NorHA) microgels. Additional microgels will be added into the guest-host hydrogel network in the hopes that once validated, this composite system can be implemented to safely transplant stem cells adjacent to drug loaded microgels to further enhance targeted therapeutic effects at the injection site for treatment of traumatic brain injury. The key focus of this project is to design and validate the injection force measurement system to ensure that the guest-host hydrogel and microgel composite can be injected safely to a region of low stiffness, such as the brain, without causing unnecessary harm, for applications of traumatic brain injury.