Bioanalytical technologies employing luminescence for astrobiology, food safety, and clinical applications

This Ph.D. research investigates the design and development of advanced biosensor technologies for applications in clinical diagnostics, food safety, and space exploration. The work focuses on integrating biosensing systems with innovative fabrication techniques, such as wax printing, 3D printing, and paper-based microfluidics, to create sustainable and high-performance Point-of-Care (POC) devices enabling rapid and decentralized analysis. A 3D-printed electrochemical ECL biosensor was developed for glucose detection using a luminol/H₂O₂ system and carbon black-doped PLA electrodes. The device operates with a 1.5 V battery and is readable via smartphone. The incorporation of glucose oxidase within an agarose hydrogel enabled the fabrication of preloaded, ready-to-use sensors that required only sample addition. The biosensor demonstrated effective glucose detection and promising potential for real sample analysis, highlighting the flexibility of 3D-printed electrochemical platforms. To enable accurate microbial monitoring in water, a DNA-based aptamer biosensor for ATP detection was also developed. In this system, ATP binding activates a catalytic DNAzyme, generating a chemiluminescent signal. Integration into origami microfluidic paper-based devices (µPADs) allowed portable, on-paper detection suitable for POC applications. The research further explores type III CRISPR–Cas systems as RNA-guided diagnostic platforms. A chemiluminescent assay was designed in which Csx1 RNase activation degrades a G-quadruplex (G4) RNA probe, reducing the luminol/H₂O₂-based signal and enabling sensitive, equipment-free nucleic acid detection. Finally, within the BOREALIS project (Biofilm Onboard Radiation Exposure Assessment Lab In Space), supported by the Italian Space Agency, microfluidic lab-on-chip systems were optimized for controlled biofilm growth under space conditions. Overall, this work demonstrates how innovative fabrication methods and molecular sensing strategies can converge to produce next-generation biosensors for healthcare, food security, and astrobiological research.