The requirements for performing chemical analysis in the field can be very challenging. Generally trade-offs are made in optimizing for size, weight, power, and performance. The need addressed here is the capability to analyze complex chemical samples in field environments for DoD applications in chemical defense and for preventive medicine. The focus is on chemical weapons, environmental toxins, and drug compounds. Though GC/MS has the capability to meet these requirements, current models are generally too cumbersome, do not perform to adequate sensitivity, specificity, or speed requirements, or do not accommodate a range of sample collection methods needed to perform specific tasks.

Syagen has adapted the advanced photoionization (PI) / QitTof MS technology of the Radiance Pro into a field-portable system called the FieldMate. Developed for high-performance, real-time analysis in the field, the FieldMate permits direct air and liquid sampling using the PI source. It also accommodates a flash GC interface for more detailed analyses using an optional EI source. The combination of PI and EI in a single instrument offers tremendous flexibility, allowing FieldMate to conduct rapid screens of mixtures by PI and subsequent confirmatory analysis by GC/EI MS.

One version of the FieldMate shown below was developed for the DoD to perform rapid and continuous monitoring for Chemical and Biological Defense (CBD). The chemical weapons (CW) capabilities of the PI / QitTof MS platform have been demonstrated in the Radiance Pro^® CW. The FieldMate is further equipped for biological weapons (BW) detection by employing a pyrolysis/GC front end for breaking down BW agents, such as bacteria and viruses, in to chemical signatures and analyzing them in two-dimensions by GC/MS. The use of PI and QitTof is crucial for obtaining clear and distinct signature information.

The combination of Py/GC with PI/QitTof MS has been demonstrated to be able to differentiate between most biological particles (BW surrogates). The figure below shows some of the signatures (selected ion monitoring chromatograms) for bacillus globuli (BG) a gram positive bacterial spore and anthrax surrogate vs. erwinia herbicola (EH) a gram negative vegetative bacteria. Clearly there are similar signatures as would be expected reflecting the similar biological material in different entities; however, there are also distinctly different signatures that are repeatable and reproducible. Notice that fast GC is used here with peak widths of less than 1 s and total analyses times of about 2 min. Also the peaks are well resolved because of the fast data acquisition rates of the QitTof, which can record full mass spectra at up to 60 Hz (20 Hz for the example below).

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