The latest episode in the American Chemical Society's (ACS') award-winning Global Challenges/Chemistry Solutions podcast series reports 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.
Based on a report by Yehuda Zeiri, Ph.D., and colleagues in ACS' The Journal of Physical Chemistry C, the new podcast is available without charge at iTunes and from www.acs.org/globalchallenges.
In the new episode, Zeiri explains 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 alerts agents to any explosive residues on the swab material.
Common explosives like TNT are solids at room temperature, so the best way to detect them is to search for particulate traces that rub off onto 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 the swabs so they would pick up even smaller amounts of explosives.
The scientists used a so-called atomic force microscope to measure how much the explosive particles stuck to different self-assembled monolayers. They concluded that swab fabrics could be improved to collect smaller amounts of explosives by peppering them with hydroxyl, phenyl and amine functional groups. They believe that such additions could enhance the binding between the swab and irregularly shaped explosive particles.
Global Challenges/Chemistry Solutions is a series of podcasts describing some of the 21st century's most daunting problems, and how cutting-edge research in chemistry matters in the quest for solutions. Global Challenges is the centerpiece in an alliance on sustainability between ACS and the Royal Society of Chemistry. Global Challenges is a sweeping panorama of global challenges that includes dilemmas such as providing a hungry and thirsty world with ample supplies of safe food and clean water, developing alternatives to petroleum to fuel society, preserving the environment and ensuring a sustainable future for our children and improving human health.
Source: http://www.acs.org/