MSc Thesis Defense: Elaheh Yousefimiab, DESIGN AND FABRICATION OF A LIGNIN-BASED IMPLANTABLE PATCH
DESIGN AND FABRICATION OF A LIGNIN-BASED IMPLANTABLE PATCH
Elaheh Yousefimiab
Materials Science and Nano Engineering, MSc Thesis, 2025
Thesis Jury
Prof. Gözde İnce (Thesis Supervisor)
Prof. Güllü Kızıltaş Şendur
Prof. Fatma Seniha Güner
Date & Time: December 17th, 2025 – 02:00 PM
Place: FASS 2031
Zoom Link: https://sabanciuniv.
Keywords : Hernia repair, Lignin, Sulfonated PEEK, Electrospinning, Biodegradable Polymers
Abstract
Hernia repair commonly relies on synthetic meshes that may cause long-term complications such as chronic pain, infection, or foreign-body reactions. To overcome these limitations, this study presents a lignin-based double-layer electrospun patch that integrates both biodegradable and non-degradable functional layers. The degradable layer was fabricated from sulfonated polyether ether ketone (SPEEK) blended with lignin, while the permanent support layer consisted of a polycaprolactone (PCL), polytetrafluoroethylene (PTFE), and lignin composite. Electrospinning enabled the formation of nanofibrous structures that support soft-tissue integration. The SPEEK/lignin layer exhibited controlled degradation over 45 days in PBS and showed no cytotoxicity. Its degradation was governed by hydrolytic chain scission, loss of sulfonic acid groups, and gradual lignin leaching, which weakened hydrogen bonding and π–π interactions within the polymer network. These chemical changes corresponded with morphological transitions such as fiber swelling, thinning, and pore formation. The non-degradable PCL/PTFE/lignin layer demonstrated long-term structural stability, strong tensile properties, and less than 9% mass loss after 10 months, providing reliable reinforcement for the abdominal wall. Incorporating lignin as a natural, sustainable, and cost-effective polymer improved environmental impact while enhancing biocompatibility. The developed double-layer patch offers a promising alternative to conventional meshes by combining temporary biodegradable support, potential for controlled drug release, permanent mechanical stability, and sustainable material design. This work highlights the potential of lignin-based nanocomposites for next-generation implantable materials for hernia repair.
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