Scientists from Stanford University in the US have devised an easy-to-use and sensitive sensor, which could be used in identifying toxic gases which are present in urban regions.
A combination of three structures could detect and differentiate between eight toxic gases
Industrial facilities and also agriculture farms often emit gases such as ammonia, sulfur dioxide and chlorine. It is a challenging task to differentiate the gas molecule structures as they are extremely simple and small in size. Hence costly equipments to be used in labs are needed for the identification of such contaminants in urban environments.
Stanford University researchers headed by Eric Kool have developed a sensor based on the DNA structure with base pairs being substituted by one of the four fluorescing aromatic monomers. This DNA structure was found to be stable when the monomers were placed one over the other. They used four sensing molecules in the structures, which gave out a pattern of fluorescence outputs for differentiating between a mix of toxic gases. The team tried out all the 256 possible structures based on monomer combinations and then evaluated their ability to both detect and distinguish a total of eight toxic gases. They decided on a combination of three of the structures for identifying and distinguishing between all the gases with the help of a series of fluorescence outputs. According to Kool, lesser number of sensor compounds could give a variety of responses.
Robert Haner, who is a specialist in DNA based fluorescent molecules at the University of Bern in Switzerland has revealed that this approach for detecting toxic gases was a stimulating one with color change profiles being highly impressive. The future plans of the team include developing other sensors using DNA scaffolds for biomedical and environmental applications.
Source: http://www.rsc.org