Biological estimate of safe packaging through 3D-Bioprinted models

Food packaging is critical for product safety, integrity, and efficient handling from production to consumers. However, food contact materials (FCMs) can release toxic chemicals into food, posing health risks such as endocrine disruption, cancer, and cardiovascular issues. Current toxicological testing focuses on individual substances, overlooking the complexity of chemical mixtures and non-intentionally added substances (NIAS). Currently, in vitro assays and animal testing are used, but they face limitations in replicating human systems and ethical challenges, emphasizing the need for innovative testing methods. Three-dimensional (3D) bioprinting offers a promising alternative by creating tissue-like constructs for more accurate toxicity screening. Using bioinks like methacrylated gelatin (GelMA) and collagen, this thesis explored ways to improve the mechanical stability, biocompatibility, and printability of hydrogels. An interpenetrating polymeric network (IPN) of GelMA and collagen was developed, exhibiting enhanced stability under dynamic conditions. Tyrosine-modified alginate hydrogels were also studied for enzymatic crosslinking, providing a safer and cell-friendly bioprinting approach. Additionally, a novel polymerization method, Frontal Polymerization (FP), was applied to synthesize semi-IPN hydrogels with tunable properties. Two 3D bioprinted liver models were developed for toxicity testing. The first combined GelMA-alginate IPN bioink with HepG2 cells, demonstrating stability and metabolic activity under dynamic conditions. The second model used decellularized liver extracellular matrix (dECM) with GelMA, showing superior metabolic activity and hepatotoxicity assessment accuracy compared to 2D cultures. This project characterized plastic packaging materials, identified migrating substances, and optimized hydrogels for 3D bioprinting. The advancements in hydrogel formulations and bioprinted liver models contribute to safer packaging assessments and more accurate toxicity testing, paving the way for improved biomedical applications and tissue engineering.