The scientific and technological advances of recent decades have brought incontestable benefits to society but have also resulted in serious environmental challenges. Among these, the presence of organic micropollutants such as pesticides and antibiotics in surface and wastewater stands out. These compounds, listed by the European Union in the Water Watch List, are often detected at very low concentrations (ng/L to µg/L). Even at trace levels, they can affect non-target organisms and compromise water quality for human consumption and reuse. Currently, the detection and quantification of these contaminants essentially rely on reference analytical techniques such as Liquid or Gas Chromatography coupled with mass spectrometry (LC/GC-MS). Despite their high accuracy and reliability, these methods present significant limitations: they are expensive, require highly specialized personnel, and are not suitable for in-field monitoring or large-scale rapid screening.
In this context, there is an urgent need to develop practical, sensitive, portable, and reusable tools that allow for the direct monitoring of micropollutants in aquatic environments. Surface-enhanced infrared absorption spectroscopy (SEIRA) is a promising technique that combines high sensitivity with the potential for miniaturization. However, its effectiveness depends heavily on the substrates used to enhance the signals. Nanotechnology, and particularly quantum dots (QDs), offers an innovative path forward, as these nanomaterials possess unique optical properties that make them excellent candidates for signal amplification.
NanoSEIRA aims to explore this approach by developing nanosensors based on silver- and copper-based quantum dots (Ag and Cu-QDs), prepared according to the principles of Green Chemistry, thus avoiding heavy metals, organic solvents, and toxic reagents. The QDs will then be functionalized with macromolecules and molecularly imprinted polymers (MIPs) to enhance their selectivity and specificity in the detection of environmentally relevant micropollutants.
One of the most innovative aspects of NanoSEIRA lies in the creation of reusable SEIRA platforms, namely: (a) the integration of QDs into magnetic activated carbon (MAC) produced from brewery industry residues, thereby promoting circular economy principles and ensuring environmental sustainability; and (b) the covalent deposition of QDs onto silicon ATR substrates, creating portable, highly reproducible sensors suitable for direct field applications.
To achieve the project goals, NanoSEIRA is structured into 7 interconnected tasks, covering the synthesis and functionalization of QDs, the development of reusable platforms, their validation in real samples, and the dissemination of the results. The project will be carried out by a multidisciplinary team from the Department of Chemistry and CESAM at the University of Aveiro, in collaboration with leading international researchers from the Federal University of Pernambuco and the University of Campinas (Brazil), the University of Ulm (Germany), and the Institute of Carbon Science and Technology (CSIC, Spain).
Through this approach, NanoSEIRA aims not only to provide a scientific and technological innovation in environmental monitoring, but also a practical and sustainable response to one of today’s greatest global challenges: water quality preservation. By developing accurate, rapid, low-cost, and reusable sensors, the project contributes to more efficient water resource management, fosters the safe reuse of wastewater, and aligns directly with the United Nations Sustainable Development Goals (SDG 6 – Clean Water and Sanitation; SDG 12 – Responsible Production and Consumption) as well as with national and European strategies for green transition and circular economy.
