Abstracts

Bioluminescence (BL) is a fascinating phenomenon in which photons are emitted as byproduct of a chemical reaction occurring in living organisms, including bacteria, fireflies, and several marine species.BL systems possess remarkable features, such as high quantum yield and no need for an external light source, that render them highly valuable bioanalytical tools for developing portable biosensors for monitoring molecules, cells, and bioactivities with applications spanning from agro-food to clinical fields. Therefore, bioluminescent biosensors have a great potential to support the “One Health” approach, to guarantee health to humans, pets, wildlife and our environment. Here we report the development of novel BL tools and strategies which can be used to improve the analytical performance of paper-based smartphone biosensors. BL showed suitable to develop highly sensitive biosensing paper platforms enabling the detection of target analytes down to the ppb levels in complex biological matrices such as environmental and clinical samples. Cell-biosensors, enzyme biosensors and cell-free systems were implemented on paper using the smartphone as detector. The stability of these biosensors has been increased by the obtainment of bio-nanocomposites relying on nanomaterials (metal-organic framework, MOF), thus improving the robustness of the analytical platforms.Moreover, we explored the combination of bioluminescence biosensing with microfluidic thread-based analytical devices (μTADs), which represent a sustainable and low-cost alternative to paper based biosensing, especially to handle very low volumes of samples (less than 5 µl), showing great potential also for multiplex analysis in combination with chemiluminescence. We report a proof-of-principle application of bio-chemiluminescence biosensing on cotton threads and, to prompt future applications in point-of-care and point-of need settings, we exploited smartphone detection enabling easy detection of the bio-chemiluminescent signal directly on the thread. The implementation of artificial intelligence (AI) algorithms to smartphone-based bioluminescence detection is also reported for the first time. We developed a paper-based toxicity smartphone biosensor which provides, thanks to an Android AI mobile app, quantitative and user-friendly information.