BME Master’s Defense Announcement for Samantha Eryn Mei Campbell (J. Linnes, advisor)

Everyone is invited to attend the public presentation beginning at 2:00 PM.

Title: Effects of Sterilization Methods on Methacrylated Hyaluronic Acid Hydrogel Microneedles

Date: November 25, 2025

Time: 2:00 PM

Location: MJIS 2001 and Zoom - https://purdue-edu.zoom.us/my/jlinnes

Committee members: Dr. Jacqueline Linnes (chair), Dr. Tamara Kinzer-Ursem, and Dr. Taimoor Hasan Qazi

Abstract:

Located just beneath the skin’s surface, interstitial fluid (ISF) contains a variety of analytes that serve as biomarkers for diseases. Hydrogel microneedles (HMNs) can extract analytes rapidly and painlessly from the dermal layer, making them a minimally invasive point-of-care (POC) diagnostic. Methacrylated hyaluronic acid (MeHA) hydrogels were used because of their fast swelling and biocompatibility. The crosslinking nature of this hydrogel makes it tunable for targeted analyte uptake. This work contributes to the broader effort to develop an MeHA hydrogel microneedle platform for cortisol uptake in depression treatment monitoring. To translate these devices toward clinical testing, an effective sterilization method that reduces the risks of infection without compromising the mechanical and swelling properties of the hydrogel is needed. Although HMNs are minimally invasive, microneedle insertion breaks the skin barrier which can introduce pathogens into the body. Considering that MeHA hydrogel is sensitive to temperature and moisture, conventional sterilization methods, such as autoclaving, can impact hydrogel structure and performance. Vaporized hydrogen peroxide (VHP) sterilization was explored in collaboration with the Purdue University College of Veterinary Medicine. This approach aimed to successfully eliminate microorganism while preserving the hydrogel’s properties. The results of this work present VHP sterilization as a viable method for preparing MeHA hydrogel microneedles for translation to clinical testing.