(178v) Comparison of Automated and Manual Layer-By-Layer Techniques for the Preparation of Heparin/Collagen Coatings and Study of Their Stability

Peripheral nerve injuries represent a significant challenge in clinical practice, often requiring surgical intervention for repair. While autografts have traditionally been the gold standard for nerve repair, they come with inherent limitations, including donor site morbidity and the need for additional surgeries. Nerve guide conduits (NGCs) have emerged as a promising alternative because of their crucial role in nerve regeneration. However, due to their surface properties, the efficacy of NGCs is often limited particularly to injuries of no more than 1-2 cm in length. Layer-by-layer (LbL) assemblies offers a versatile approach for surface modification of NGCs, allowing for the incorporation or controlled release of bioactive molecules such as growth factors and other extracellular matrix components. In this study, we focus on the development and characterization of HEP/COL coatings using both automated and manual LbL techniques. Heparin (HEP) and collagen (COL) are chosen as the building blocks for increased biocompatibility and binding abilities. Specifically, we investigated the stability of the automated and manual coatings over time and their ability to enhance the biological behavior of different cell lines. Schwann cells were used to assess the bioactivity of the coatings and their potential to promote cell proliferation. Our results demonstrate that automated LbL techniques offer several advantages over manual methods, including improved coating uniformity and reduced variance across cell culture plates. Furthermore, the stability of the coatings over time is found to be comparable between automated and manual techniques, with both exhibiting sustained increase in cell proliferation and adhesion. These findings have important implications for the development of NGCs as delivery systems, with the potential to enhance nerve regeneration and improve clinical outcomes for patients with peripheral nerve injuries. Overall, this study highlights the utility of LbL assemblies as a versatile platform for the development of biomimetic coatings with tailored properties for nerve regeneration applications and contribute to the ongoing efforts in tissue engineering and regenerative medicine for improving patient outcomes and quality of life.