• 3D cell cultures
• 3D printing
• 3D-Bioplotter
• Additive manufacturing
• Biocompatible systems
• Direct Ink Writing (DIW)
• Elastomer
• Graphene Oxide (GO)
• Lung epithelial cells
• Optically active systems
• Photochromic materials
• Photochromism
• Scaffolds
• Tungsten Trioxide (WO3)
• Vis-NIR spectroscopy

3D printing is a revolutionary manufacturing technology, enabling realization of 3D objects in a layer-by-layer fashion starting from a digital CAD model, capable to address various applications from tissue engineering to sensors and photonics. The purpose of this Thesis was the realization and characterization of 3D printed structures using a 3D-Bioplotter by EnvisionTEC, while investigating two transversal applications: the realization of optically-active structures and of scaffolds for biophysics applications.
Firstly, I characterized the printing process as a function of printer parameters and optimized the printing protocol. I also prepared and characterized silicone-based composite inks with graphene oxide flakes (GO) and tungsten trioxide nanowires (WO3).
Part of my work was the study of the photochromic properties of 3D printed WO3-silicone samples, which show reversible blue coloration under UV light exposure. Their photochromic properties were investigated by visible and near infrared absorption spectroscopy.
Afterward, I focused on the realization of 3D micropatterned elastomeric structures which I tested as 3D scaffolds for cellular cultures. I studied the interaction between these structures and lung epithelial cells by measuring their adhesion, proliferation, and spatial organization properties. It was found that 3D printed scaffolds can support epithelial cells growth and development, showing original and unparalleled results respect to traditional 2D cultures.