With the mass spectrometry-based instrument, a passenger’s ticket would become a passive sampling device that detects even a billionth of a gram of explosives such as nitroglycerine and TNT. The instrument works by sampling air that passes over a ticket as the paper is fed through a scanner and then identifying the chemical composition of the substances in the air. The procedure takes just a few seconds.
"If a person has been in contact with explosives, this instrument would detect it," said Gary Van Berkel, a researcher in ORNL’s Chemical Sciences Division. "Even if the person were wearing protective clothing while handling the explosives, it would still almost certainly detect it."
The beauty of the system, Van Berkel said, is that passengers would be sampled as they wait in line, thereby avoiding random checks with swabs and other less sophisticated techniques that cause delays, produce more false positives and fail to inspect 100 percent of the passengers.
"This system would allow all of the passengers to be sampled with no increase in manpower," Van Berkel said
Mass Spec Analytical’s Jonathan Langton noted that the less sophisticated machines in use in airports do not afford the same level of protection.
The unit would sell for about $250,000 initially and would become less expensive as more units were built.
Van Berkel and collaborators have already performed many tests of the instrument, which is capable of analyzing 1,000 tickets or boarding passes per hour. One of the next steps is to incorporate a simple visual display that identifies the explosive and triggers an audible alarm. Developers also plan to add an automated calibration and threshold setting that would further prevent false alarms.
No special training would be required for operators of the final product, Van Berkel said.
The effort with Mass Spec Analytical of Bristol, England, takes advantage of ORNL’s expertise in fundamental mass spectrometry and explosives vapor detection. In fact, the Organic and Biological Mass Spectrometry group has been heavily involved in explosives detection work since the late 1980s and at one point had two explosive detectors in use to sample mail at a Department of Energy site.
The task facing Van Berkel and colleagues Doug Goeringer and Keiji Asano is to help Mass Spec Analytical determine the best ionization source for the instrument. The ionization source is what ultimately enables the instrument to analyze the vapor and determine its identity.
In the short term, plans call for further testing of the instrument and gaining acceptance for field testing in the United States, Canada and England.
Looking ahead, Van Berkel envisions this technology being used to protect property by tagging it with a chemical that could be detected at portals or other check points. Other potential applications include detecting drugs, chemical and biological weapons, and detecting pesticide residue on food.
Researchers also expect related technology to be useful for performing medical diagnostics such as analyzing breath for drugs and for determining the presence or states of disease. And Van Berkel expects it to be useful for law enforcement officials for non-invasive and immediate forensic analysis of traces of gunpowder residue, explosives, drugs and traces of other illicit activity such as chemical vapors from drug labs.
Funding for this work is provided by the Department of Energy. ORNL is a DOE multiprogram research facility managed by UT-Battelle.