Nanoparticles for paper-based biosensors and environmental impact assessment

Details

Supervisors

Raskin, Jean-Pierre

Faculty

Ecole polytechnique de Louvain

Degree label

Master [120] : ingénieur civil en chimie et science des matériaux, à finalité spécialisée

Abstract

Along with climate change, population growth and intensive agriculture, water pollution is responsible for the 2.4 billion people living in water shortage areas. In such places, frequent water quality assessments are crucial to identify, control and prevent water sources contaminated with infectious diseases. To meet this need, point-of-care biosensors have the potential to bring rapid, inexpensive, and precise detection of hazardous contents in water samples. The power of such tests has been recently evidenced by the COVID-19 pandemic since they are the only reliable autotests available on the market. The project that led to this master thesis aims at developing paper-based biosensors for bacteria detection in remote area water samples. To this end, nanoparticles are used to detect the presence of such harmful organisms and send a signal to the user. Their unique properties significantly improve the performance of the tests and allow for quantitative bacteria sensing in water samples. In this work, gold and magnetic nanoparticles are investigated to open new electrical and magnetic detection opportunities for paper-based biosensors. Both were successfully synthesized, characterized, compared with commercial samples, and made ready for further conjugation with bioreceptors. Hybrids of both nanoparticles revealed very promising properties in terms of further detection possibilities. Furthermore, the analysis of the microfluidic behavior of nanoparticles in different papers revealed important non-specific binding with the fibers. Finally, to anticipate the adverse effects of such biosensors on human health and ecosystems when produced on an industrial scale, the environmental impacts of the papers, nanoparticles and plastics used were assessed at large scale. Nanoparticles were observed not to be the most impacting component of the biosensor and to only have significant toxic effects at very high concentrations. In addition, eco-design solutions were proposed to push the biosensors towards a more responsible solution to the urgent situation of global water scarcity.