Advanced Sensors Detect Chemical Weapons in Seconds 

Scientists at Queen’s University Belfast are developing new sensors to detect chemical agents and illegal drugs which will help in the fight against the threat of terrorist attacks. The devices will use special gel pads to ‘swipe’ an individual or crime scene to gather a sample, which is then analyzed by a scanning instrument that can detect the presence of chemicals within seconds. This will allow better, faster decisions to be made in response to terrorist threats.

The scanning instrument will use Raman spectroscopy which involves shining a laser beam onto the suspected sample and measuring the energy of light that scatters from it to determine what chemical compound is present. It can measure particles of a miniscule scale, making detection faster and more accurate.

Normally, this type of spectroscopy is not sensitive enough to detect low concentrations of chemicals. So, here the sample is mixed with nanoscale silver particles, which amplify the signals of compounds allowing even the smallest trace to be detected.

Steven Bell of the School of Chemistry and Chemical Engineering at Queen’s University of Belfast is leading the research. He said: “Although we are still in the middle of the project, we have finished much of the preliminary work and are now at the exciting stage where we put the various strands together to produce the integrated sensor device. For the future, we hope to be able to capitalize on this research and expand the range of chemicals and drugs which these sensors are able to detect.”

It is hoped the new sensors also will be the basis for developing ‘breathalyzer’ instruments that could be of particular use for roadside drugs testing in much the same way as the police take breathalyzer samples to detect alcohol. At present, police officers are only able to use a field impairment test to determine if a person is driving under the influence of drugs. The accuracy of this method has been questioned because of concerns that it is easy to cheat.

To ensure the technology is relevant, senior staff members from Forensic Science Northern Ireland (FSNI) will give significant input into the operational aspects of the technology and give feedback as to how it might be used in practice by the wider user community.

Stan Brown, Chief Executive of FSNI said: “We consider the work being carried out by researchers at Queen’s University extremely important and potentially very useful in driving forward the effectiveness, efficiency and speed of forensic science practice. The combination of leading-edge research and hands-on experience of FSNI’s practitioners has already proven very fruitful and is likely to lead to significant developments in forensic methodologies across a range of specialisms.”

In the future, this technology could have a number of important applications and, according to Bell: “There are numerous areas, from medical diagnostics to environmental monitoring, where the ability to use simple field tests to detect traces of important indicator compounds would be invaluable.”

The research is being conducted in collaboration with colleagues from the School of Pharmacy at Queen’s University and Forensic Science Northern Ireland. Since 1999, this collaboration has been focused on developing new Raman and SERS methods for analysis of illicit drugs, paints, fibres, materials and other physical evidence. It has already led to routine use of Raman methods within FSNI laboratories for drugs intelligence and a more extensive program for integrating Raman methods into a broad range of casework is already underway. This new project will take the next step and move this research out of the laboratory and into the field.