The product of terrorism is fear, and one of the most frightening threat scenarios facing emergency responders is the release of a dangerous biotoxin in a large public space, such as a crowded stadium, tunnel, shopping mall or train station.

The key to treatment for those exposed to such agents is speed, yet no reliable method currently exists for quick, efficient diagnosis of human exposure.

That could change soon. Scientists at Sandia National Laboratories in California are working on a small, portable microfluidic device that they believe will be able to rapidly detect biotoxin exposure from a small blood sample.

"This device is based on microfluidics, which allows detection of several biotoxins simultaneously, even with a very small blood sample," said University of Massachusetts–Dartmouth chemistry professor Bal Ram Singh. UMass-Dartmouth is a partner is the Sandia research.

Microfluidics, which dates to the early 1980s, has been used in the development of "lab-on-a-chip" technology and, most commonly, in inkjet printheads.
Simultaneous detection of toxins is important under intentional exposure conditions when one would otherwise have to guess which of many potential biothreat agents should be the target for treatment.

The device will be able to detect toxins including botulinum toxin, staphylococcal enterotoxin B and shiga toxins. Shiga toxins are produced by, among other bacteria, Shigella dysenteriae and some serotypes of E. coli, including O157:H7.

Instead of sending those suspected of being infected with a biotoxin to a medical facility, where lab results could take days or weeks, the researchers say, on site emergency responders would use this device to draw blood samples and make a rapid determination as to the type of exposure.

Then those in need of treatment could be monitored, and countermeasures could be immediately taken to mitigate further damage.

Singh told Homeland1 that the planned device is being fitted with chemistry that will also be able to distinguish between "live" and "dead" (denatured, or functionally inactive) toxins to avoid false alarms, at least in case of botulinum toxins.

The only downside to the device is that the user will need to be trained to draw blood, though that might change eventually if a more accessible and readily available specimen such as saliva or perspiration were used to provide samples in place of blood.