Progettazione, sviluppo e validazione di una piattaforma microfluidica per la generazione di gradienti di farmaci per il trattamento di tumori

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive and difficult-to-treat malignancies, characterized by a high degree of tumour heterogeneity and resistance to conventional therapies. Microfluidic systems, commonly referred to as "organ-on-a-chip" platforms, represent a promising approach for the development of personalized therapeutic strategies. These microscale devices enable precise control of fluid flow, chemical gradients, and cell culture conditions, offering high experimental reproducibility with minimal sample and reagent consumption. The present work, carried out at the BIAMET laboratory, aims to design, fabricate, and validate a microfluidic platform capable of generating controlled drug concentration gradients for patient-specific drug screening. Patient-derived pancreatic tumour organoids (PDOs) are employed as biological models to assess the therapeutic response. The report is organized into three chapters. The first provides an overview of the state of the art in microfluidics and introduces the SPOTTED platform, along with the fabrication techniques employed. The second chapter describes the design and fabrication of both the microfluidic chip and the microwell module, encompassing CAD design, computational simulations via COMSOL Multiphysics®, photolithography, and 3D printing. The third chapter presents the experimental results, evaluating the platform's ability to generate a stable concentration gradient and the efficacy of the bonding between the microfluidic chip and the microwell. The experimental results demonstrated that the platform is capable of generating a stable and reproducible concentration gradient, with six distinct concentration levels ranging from 0% to 100%, as confirmed by both fluorescence microscopy and spectrophotometric analysis. Plasma bonding proved to be the most effective assembly method, ensuring a leak-free interface between the PDMS layers. The microwell module successfully retained patient-derived organoids under flow conditions, although occasional spheroid displacement was observed, suggesting that further optimization of the well geometry is required. Overall, the platform represents a promising tool for drug screening applications, with potential for future extension to other tumour models.