Nanotechnology to detect contaminants in water
The Catalan Institute of Nanotechnology is developing faster, easier and more affordable electrochemical and optical detection techniques.
BY BIOCAT
Breakthroughs in nanotechnology, applicable in a wide variety of sectors, create new alternatives for detecting heavy metals like cadmium, lead, copper and mercury in both fresh and salt water. The Catalan Institute of Nanotechnology (ICN) —which belongs to the network of Government of Catalonia Research Centers (CERCA)— is working to develop and apply two different techniques to detect contaminants using nanomaterials:
Electrochemical detection using nanostructural carbon electrodes. These devices, connected to a potenciostat, are used to take measurements so that, using a screen, electric signals or analysis results can be read. The device and measurement instrument, thanks to their small size, are easily transportable and can be used on location, avoiding large, sophisticated instruments currently used in laboratories to this end. This technology has great potential for real applications like measuring sea contamination levels: a sensor is installed on a platform, which uses wireless communication to warn of possible contamination.
Optical detection is based on changes in the color of gold nanoparticles that are used to trap contaminating metals. This technique, which is simpler than the previous one, at the moment has only been tested in the laboratory. It doesn’t require any type of device, just synthetic modified nanoparticles for selective capture of contaminant molecules. It is less sensitive but it is easier to use and, therefore, has a wider range of possibilities.
These new contamination detection techniques using nanomaterials are, according to the ICN, faster, easier and more affordable. There are a number of fields where they could be applied, such as industrial wastewater, clinical treatment (detecting metals in blood), and food safety, among others.
Development of these new heavy-metal detection techniques was the subject of the doctoral thesis written by Gemma Aragay, a researcher in the Nanobioelectronics and Biosensors Group at the ICN, led by ICREA professor Arben Merkoçi in collaboration with Dr. Josefina Pons from the Autonomous University of Barcelona. Part of these studies have recently been published in the prestigious journal Chemical Reviews.