Resumen de Development of bimodal waveguide interferometric sensors for environmental monitoring
This Doctoral Thesis is devoted to the development of novel nanophotonic sensors as alternative solutions for the existing environmental monitoring tools currently employed. In particular, we propose the use of a novel interferometric sensor, the bimodal waveguide interferometer device (BiMW), for the selective, sensitive, rapid and direct analysis of pollutants present in the marine and the air environments.
For the detection of pollutants in different media, air and water, two strategies have been followed. The first approach was the development of a biosensor device based in a competitive immunoassay for the detection of traces of a pesticide directly in seawater. To achieve this objective, we started with an in-depth study of different biofunctionalization strategies because the surface chemistry needs to be optimized to maximize the stability, reproducibility and sensitivity of the competitive immunoassay. Another crucial step for the development of the pesticide biosensor was the optimization of the immunoassay conditions. Our final immunosensor overcomes some of the constraints of the current analytical techniques and offers an advanced analytical tool for the real-time and on-site monitoring of water pollution control.
The second strategy proposes the integration of Metal-Organic Frameworks (MOFs) as receptors to develop a chemical sensor for the detection of small molecules such as gases. First, the type of MOF and the integration in thin films were evaluated and optimized. Then, the developed MOF-BiMW gas sensor was assessed in terms of sensitivity, selectivity, reproducibility and stability. Results show that this new sensor overcomes some of the drawbacks of the current methodologies for gas sensing.
This work has opened the path of a new research line for the real implementation of advanced environmental monitoring sensing tools.
