Development of an Evaporation-Based Preconcentrator for Trace Detection in Defense Applications

Y. Su and T. Hutter
The University of Texas at Austin, Texas, United States

Keywords: Evaporation, preconcentrator, biochemical detection, microfluidics, portable analysis

Detecting tiny amounts of harmful (bio)chemicals, such as anthrax spores, nerve agents or toxic industrial chemicals (e.g., benzene or pesticides), is important for defense and security operations. This project focuses on developing a device that uses evaporation to concentrate chemical and biochemical compounds in an aqueous sample, making them easier to detect using portable instruments. The device works by using small pores to control the evaporation process, allowing it to collect and concentrate substances from very dilute solutions. By carefully controlling how heat and liquid move during evaporation, accurate quantification of concentration is possible. The design includes microfluidic features that boost the evaporation rate by increasing the surface area exposed to the liquid. Laboratory tests have shown that this approach is highly effective at concentrating with factors up to 10-fold. The small size of the device also makes it easy to pair with portable detection instruments used in the field, which is important for quick, on-the-spot analysis in defense situations. The preconcentrator device improves sensitivity and specificity, can be used with any portable test for qualitative and quantitative analysis in the field.