Of all the threat scenarios facing emergency responders around the country, the release and spread of a dangerous biotoxin in a large public space is one of the most troubling.
The reason is simple. Though early diagnosis of biotoxin exposure is important for consequence mitigation and the key to saving lives, no current method exists for the quick, efficient detection of such poisonous agents.
That could all change one day soon, as researchers at Sandia/California have secured funding from the National Institute of Allergy and Infectious Diseases (NIAID) to design and engineer a small, portable microfluidic device that will offer rapid detection of biotoxin exposure in humans. In addition to speed, the device promises to offer high sensitivity, the capability to detect both presymptomatic and symptomatic markers, and ease of use.
The NIAID, part of the National Institutes of Health (NIH), has committed $3.2 million to the five-year project. Sandia is leading the effort in collaboration with B.R. Singh at the University of Massachusetts at Dartmouth and Steve Binder at Bio-Rad Laboratories. Anup Singh (8321) is the principal investigator for Sandia.
Device designed for point-of-care and point-of-incident settings
Instead of sending those suspected of being infected with a biotoxin — spectators at a sporting event who have been contaminated by a terrorist release, for example — to a medical facility where lab results could take days or weeks, Anup says a lightweight, portable device would allow onsite emergency personnel to draw blood samples and make a rapid determination as to the degree of exposure. Those in need of treatment can then be monitored, and countermeasures can be immediately executed at the facility to mitigate further damage.
“It could be a firefighter, a paramedic, or simply a primary care practitioner who might use this device one day,” says Anup. “The only stipulation is that the device’s end user will need to be authorized and trained in drawing blood, though that could change eventually. In the not-so-distant future, a more accessible and readily available specimen such as saliva might be able to diagnose toxins.”
Currently, says Anup, the technology to quickly test individuals for biotoxin exposure does not exist. Those suspected of being infected must give blood samples at a medical facility and wait for laboratory analysis. The device will be able to detect toxins including botulinum toxin, SEB (Staphylococcal Enterotoxin B), shiga toxins, Clostridium perfringens epsilon toxin, and others.
Builds upon success of saliva-based diagnostics project
The project builds upon the success of Sandia’s well-known “spit project,” a program also funded by the NIH (see Jan. 27, 2005, and April 13, 2007, Lab News). That project could allow dentists to one day quickly test patients for gum disease and other afflictions via saliva samples.
Bioengineer and microfluidic expert Anson Hatch (8321) will lead the microfluidic assay development effort. The system will incorporate microfluidic methods developed by Anson and others at Sandia that facilitate hands-free analysis by integrating sample pretreatment with electrophoretic immunoassays that quickly measure analyte concentrations in blood. The self-contained device will consist of miniaturized electronics, optical elements, fluid-handling components, data acquisition software, and a user interface.
The technology, device, and methods, says Anup, can also be extended to detection of biomarkers of other systemic diseases and conditions such as cancer and cardiovascular disease.