25 November 2005: Microparticle sampling for direct biohazard detection

An important step towards portable sensors for airborne bacteria and toxic chemicals has been taken by US researchers. 

Yuejun Zhao and Sung Kwon Cho of the Department of Mechanical Engineering, University of Pittsburgh, have devised a new method for sample collection which can be used with lab-on-a-chip analysis systems.

Lab-on-a-chip devices are capable of directly measuring airborne particles. These systems are portable, use extremely small amounts of sample and reagents, and can provide fast, automated analysis, with excellent sensitivity and selectivity. Current particle samplers use large volumes of liquid and require numerous manual handling steps, and are impractical for use with automated, small volume lab-on-a-chip devices.

Measurement of particles in the air is highly important from both public health and national security perspectives. Such biological particles can cause a wide variety of respiratory diseases and other adverse health effects. Recently, there has also been increased concern about the use of biological warfare agents such as anthrax in terrorist attacks. Conventional methods for monitoring airborne bacteria are prone to error and involve complex, time consuming processes that must be carried out by skilled technicians.

Zhao and Cho say their method will eliminate manual handling of particle collection media and so improve the performance of sample processing. They hope that the new technique will enable a fully automated portable monitoring system for airborne microorganisms.

Christopher P Ingle