Technology Used By Defiant Technologies

All of the technology is made using microfabrication processes for low power hand held operation.

Smart Selective chemical precon- centration: Defiant uses preconcentrator technology that is capable of sensing when it has collected a sufficient amount of sample for analysis. If the ambient concentration is low, the device will collect for a longer period of time, if it is higher, the collection time is lowered automatically on the fly. In addition, the selective sol gel films used on this device ensure that chemical interferences like diesel and humidity aren't introduced into the analysis system.	1st Stage Selective Preconcentration As can be seen above, 3 chemicals enter but only 2 are collected. This can be due to either designed physical attributes of the device or a designed chemical interaction.

Micro Gas Chroma- tography: Defiant uses a LIGA fabricated GC column that will separate both target and interfering chemicals away from one another. In this fashion, the detector only senses one chemical at a time since the chemicals arrive at the detector at different times.	2nd Stage Micro Gas Chromatography The picture above shows the GC column separating two target chemicals. As they pass through the column the red is retained more because it has a higher affinity for the polymer that lines the column.

Selective Detection: Defiant uses arrays of surface acoustic wave SAWs detectors and pivot plate resonators (PPRs). Each element in these arrays can be coated with a variety of different films to provide an array response that is specific to the class of chemical it senses.	3rd Stage Selective Detection Since the blue chemical exited the GC column first, its reaches the detector first. The red is sensed seconds later. Shown above is a cartoon of our PPR which "weighs" the chemical as it passes by the detector. A polymer deposited on the surface promotes sorption of certain chemicals and therefore promotes their detection.

Peeling the Onion: Each stage of Defiant's chemical analysis system peels away layers of uncertainty. The smart selective preconcentrator actually ignores interfering chemicals. The GC column will retain different target chemicals for different periods of time so that they leave the column at different times. Then the detector provides a response pattern that is indicative of the class of chemical sensed.

Affordable chemical detection systems: Using batch fabrication processes that are analogous to how computer chips are made, Defiant produces the key components of its systems. This helps to keep the cost low. Batch cleaning process and coating processes are also employed.