Project Acronym: SAFE WATER

Full title: On chip whispering gallery mode optical microcavities for emerging microcontaminant determination in waters

Project duration: 45 months
Coordinator: Institute of Applied Physics “Nello Carrara” – National Research Council (IFAC-CNR)

Contact: Simone Berneschi (s.berneschi@ifac.cnr.it or bernes@ifac.cnr.it)

Project website address: http://www.iet.unipi.it/safewater/Home.html

Executive summary

In the last decades, the rapid growth of the world population and the increase in industrial and agricultural activities have contributed to a continuous depletion of the water resources quality, endangering the health of individual citizens especially when water is destined for human consumption. As highlighted in recent European directives on the quality and monitoring of the water environments (EU 2013/39 and EU 2015/495), particular attention is paid to emerging microcontaminants (EMCs such as drugs, hormones, personal care and life-style products) which, present in traces in the aqueous matrices, are poorly biodegradable and difficult to remove through conventional treatment processes. It becomes essential to have an analytical method that can detect the presence of these pollutants at low concentrations. Based on the synergy among different competences of the consortium partners in the field of chemistry, electronics, photonics, microfluidics, the aim of the project is the realization of a new portable optical instrument for in situ and multiplexing detection of different EMCs. The absolute novelty of the prototype consists in the use of hollow-core whispering gallery mode microcavities which, with their high Q factor values, ensure extremely low limit of detections. The selected recognition strategies will be based on the chemical modification of inner surface of the microresonators or by molecular imprinting polymers (MIPs) or by functionalization process with specific antibodies. Finally, the various microfluidic and optoelectronic modules will be integrated into a single chip, controlled by an external PC for data acquisition and processing, establishing an innovative pollution monitoring system.

Final project summary

The rapid growth of the world population and the increase in industrial and agricultural activities have contributed to the continuous depletion of the water resources quality, endangering the health of individual citizens mainly when water is destined for human consumption. As highlighted in recent European directives on the quality and monitoring of the water environments (EU 2013/39 and EU 2015/495), particular attention was paid to emerging contaminants (EMCs, such as drugs, hormones, personal care, and lifestyle products). These, if present in traces in the aqueous matrices, are poorly biodegradable and difficult to remove through conventional treatment processes. It becomes essential to have an analytical method that can detect the presence of these pollutants at low concentrations. Based on the synergy among different competences of the consortium partners in the field of chemistry, electronics, photonics, microfluidics, the aim of the SAFE WATER project was the realization of a portable instrument for in situ and multiplexing detection of different EMCs (i.e.: estrone, glyphosate). The absolute novelty of the prototype involved the use of whispering gallery mode (WGM) microcavities, which, with their high Q factor values, ensured the extremely low limit of detections. The selected recognition strategies concerned the chemical modification of the surface of the WGM microresonators, both with molecularly imprinted polymers (MIPs) and with specific antibodies. The related analytical protocols were implemented and validated together with the relevant subsystems (i.e.: the optoelectronic control unit; the optofluidics platform) constituting the SAFE WATER prototype. The modular nature of these individual parts can contribute to make easy their assembly into a portable sensing instrument. This allows to carry out in situ measurements in a short time, eliminating the high costs and the long waiting times associated with the use of centralized laboratories.