Boosting the sensitivity of airport security screening

Nov 14, 2012
Boosting the sensitivity of airport security screening
New research could make explosives detection more sensitive. Credit: Transportation Security Administration

Scientists are reporting a simple way to improve the sensitivity of the test often used to detect traces of explosives on the hands, carry-ons and other possessions of passengers at airport security screening stations. Their report appears in ACS' The Journal of Physical Chemistry C.

Yehuda Zeiri and colleagues explain that most tests for traces of explosives begin by rubbing a swab made from glass fiber, Teflon or cotton over the suspect material. Analysis of the swab in a detector—usually a device called an ion mobility spectrometer—alerts agents to any explosive residues on the swab material. Common explosives like TNT are solids with very low vapor pressure at room temperature, so the best way to detect them is to search for particulate traces that rub off on clothing and luggage. To help security agencies prevent attacks more successfully, the researchers studied how explosive particles adhere to surfaces and how they could improve swabs to pick up even smaller amounts of explosives.

Boosting the sensitivity of airport security screening

Using an to measure the between explosive particles and different self-assembled monolayers, the scientists concluded that swab fabrics could be improved to collect smaller amounts of explosives by peppering them with hydroxyl, phenyl and amine . They believe that such additions could enhance the binding between the swab and irregularly shaped explosive particles.

Explore further: Researchers bring clean energy a step closer

More information: "Adhesion of Standard Explosive Particles to Model Surfaces" The Journal of Physical Chemistry C, 2012. DOI: 10.1021/jp303622n

Abstract
The adhesion of explosive particles to substrates with tailored chemical nature was analyzed by atomic force microscopy (AFM). Four different explosives were studied: TNT, RDX, HMX, and PETN. Two types of measurements were performed: in the first, a self-assembled monolayer (SAM) with different end groups was deposited on the tip and used to measure adhesion forces to an explosive particle surface. In the second type of experiment, the explosive particle was glued to the cantilever, and its adhesion force to a SAM-covered gold-plated glass substrate was measured. All experiments were performed both in ambient air and under water. The study shows that −OH and −C6H5 end groups lead to increased adhesion. In addition, we found that capillary forces have significantly contributed to the adhesion of explosive particles.

add to favorites email to friend print save as pdf

Related Stories

New NIST SRM supports the fight against terrorist bombings

May 30, 2012

The National Institute of Standards and Technology (NIST) has released a new standard reference material (SRM) to aid in the detection of two explosive compounds that are known to be used by terrorists. Researchers ...

Glowing films reveal traces of explosives

May 23, 2008

New spray-on films developed by UC San Diego chemists will be the basis of portable devices that can quickly reveal trace amounts of nitrogen-based explosives.

Silkmoth inspires novel explosive detector

Jun 01, 2012

Imitating the antennas of the silkmoth, Bombyx mori, to design a system for detecting explosives with unparalleled performance is the feat achieved by a French research team. Made up of a silicon microcantilever ...

Recommended for you

Researchers bring clean energy a step closer

Feb 27, 2015

For nearly half a century, scientists have been trying to replace precious metal catalysts in fuel cells. Now, for the first time, researchers at Case Western Reserve University have shown that an inexpensive metal-free catalyst ...

The construction of ordered nanostructures from benzene

Feb 27, 2015

A way to link benzene rings together in a highly ordered three-dimensional helical structure using a straightforward polymerization procedure has been discovered by researchers from RIKEN Center for Sustainable ...

Superatomic nickel core and unusual molecular reactivity

Feb 27, 2015

A superatom is a combination of two or more atoms that form a stable structural fragment and possess unique physical and chemical properties. Systems, that contain superatoms, open a number of amazing possibilities ...

Oat breakfast cereals may contain a common mold-related toxin

Feb 25, 2015

Oats are often touted for boosting heart health, but scientists warn that the grain and its products might need closer monitoring for potential mold contamination. They report in ACS' Journal of Agricultural and Food Chemistry that s ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.