08.05.2008
Siemens researchers are developing cell sensors that could serve as early-warning systems for contaminated water or poor air quality. A team at Siemens Corporate Technology (CT) in Munich is now working with the biotech company Bionas in Rostock on selected cell cultures adhered to silicon chips. Cell sensors are ideal for detecting contaminants, because like higher living organisms, they react to changes in their environment by altering their metabolism. The chip serves as a signal converter that immediately stores the related information in an overarching process control system and initiates measures to restore water to its previous level of quality, for example.
Many water treatment facilities currently use a trout pond or a test with water striders to determine if their chemical purification units are functioning properly. In order to eliminate any possibility of endangering public health, the drinking water regulations that have been in effect in Germany since 2003 require stricter adherence to pollution standards than was previously the case. This makes it all the more important to have an early-warning system that signals quickly and clearly when water quality deteriorates, making it possible to take corrective measures.
CT researchers are working hard to optimally mount the cells onto a silicon chip, where they need to remain and survive for about two months, while surrounded by a nutrient solution that can be continually fed with water samples. The cells are thus constantly in contact with potentially damaging substances. Three cellular reactions are evaluated by the chip: respiration, metabolism, and changes of shape. These reactions are read out by three different types of electrodes. Liver cells are particularly suited to this application, and can be obtained as cell lines from a cell database.
Plans call for the cell sensors to be used in a broad range of environmental monitoring areas. Along with controlling water quality and air quality in air-conditioned rooms, these include the monitoring of toxins and hazardous substances in public buildings. The sensor developers have realized very concrete advances for the building technicians when it comes to “green buildings,” where the focus is on using the most environmentally friendly purification processes in large buildings.
