Towards sensitive fluorescent metal nanosensors, IR range, for dual detection of nitrates in water

Abstract

In recent decades, the use of nutrients and fertilizers for agriculture has increased exponentially at a global scale with detrimental consequences on freshwater and marine ecosystems. Nitrate and Phosphate based nutrients cause serious health problems such as different forms of cancer, increasing Algae and eutrophication. Detection of these chemicals in water and soil has been a prominent field of research worldwide. In this study development of a dual sensor using both surface plasmon resonance (SPR) and fluorescence is introduced. Five different metal nanoparticles were tested in solution for spectroscopic properties and two were identified with potential as dual sensors, Egyptian blue and gold nanoparticles. The sensor will be designed to show emission in the infrared range. Subsequent results will be discussed where the nanoparticles were tethered to a glass surface using aminopropylsilane chemistry. These coatings are will not rinse off and are scratch resistant as well. The fluorescent and SPR response are both exhibited even in the form of a thin film. Future investigations will involve attachment to a prism surface and analysis of the sensitivity of the SPR and fluorescent simultaneous signal to nitrate ion in water.