Chemical detective

A hand-held near infrared (NIR) chemical detector for use in security, environmental monitoring and forensics is being developed by Welsh company

and Surrey University's

(ATI).

By miniaturising NIR technology and using a database of spectrums, the device can identify the chemical content of a substance within a few seconds on a 'point, click, read' basis.

Held about an inch away from a sample, the torch-like device shines a light for a couple of seconds and a spectrometer analyses the light reflected by the sample. Each organic chemical has a unique spectrum 'fingerprint' and the device uses these to identify the content of a sample by comparing the spectrum it receives with the 'fingerprints' held on the database.

'The device employs advanced chemometrics using multivariant analysis to determine which spectrums are present,' said ZiNIR director Tracy Nuttall. 'The device screen will then tell you exactly which chemicals — and to which concentrations — it has found within the mixture.'

The company says the detector will also provide an estimate of how reliable the reading is based on the clarity of the spectrum it has received.

Nuttall said that portable NIR units do exist but require more equipment, such as a laptop, to work. She said none provides onboard analysis, which reduces their ergonomic benefits. They also take longer to perform a full analysis.

Each application will require a different database, which the company will develop. Nuttall admitted that for some, such as security and customs, this will have to be carried out in partnership as ZiNIR does not have access to chemicals such as explosives or drugs.

The ability to take quick readings 'in the field' has particular applications in the areas of environmental monitoring and forensics.

'NIR is particularly good at recognising land contamination,' said Nuttall. 'When builders or developers want to purchase land or apply for planning permission, for example, they need to know its condition. With a hand-held device they can go out and zap 15 or 20 different areas very cheaply. It's a more cost-efficient alternative to taking that many samples and sending them to a lab.

'It could also be used in drug detection,' said Nuttall. 'NIR is good for identifying cocaine because, as a complex mixture analyser, it can tell the difference among street varieties and what they are cut with. This means the police can follow a particular trail through a town or city.'

She also said that NIR has the benefit of being a non-contact analyser and can even detect chemicals through a glass or clear plastic bottle, which is especially useful at airports.

Conservation scientists could use the device to monitor the degradation of textiles and statues. And for customs officers, instead of having static instruments to identify drugs the device could be taken around ports and even on to ships and aircraft.

As well as its partnership with the ATI at Surrey University, the project has benefited from funding from Finance Wales (WDA), the South East England Development Agency (SEEDA) and Finance South East.

ZiNIR is continuing to work with the ATI to improve the detector's optics, make the readings as sensitive as possible and the device more robust. The team is also developing new ways of reducing the weight and is working with design engineers to develop the final design of the device, currently at the mid-development stage.

It is hoped to produce test models by the end of this year and have a final product by early to mid 2009.

With demand for security technology high, Nuttall believes the detector has great potential — especially in the US.

'There the market is huge because the government wants all firefighters, police and ambulance crews to have a device capable of testing for dangerous substances,' said Nuttall. 'According to a 2004 report, the security market in 2010 will be worth around $190m in the US, and $270m globally.'