The Next Generation of Chemical/Biological (CB) Threat Detection

Many technologies have been developed for chemical weapons (CW) and biological weapons (BW) detection. Mass spectrometry offers the benefit of molecular identification. Other detectors (e.g., IMS, GC, chemical sensors, etc.) are indicators in that they give a characteristic response indicative of the target compound. For BW detection, there are some viable options to MS detection; however, for continuous real-time monitoring, MS has clear advantages. There are three general technologies for BW detection:

• Mass spectrometry (MS) offers molecular fingerprinting and rapid analysis. Effective MS analysis requires a sampling system that can collect the particles and effectively lyse the microorganisms to release the molecular signature content within.
  
  
• Polymerase chain reaction (PCR) can be used to characterize BWs. As with MS, a sampler and method to release the DNA fragments is needed. PCR sequencing is a slower method than MS and is not well suited to detection of viruses and biotoxins.
  
  
• Immunoscreening with antibodies can be used to selectively bind to exposed antigens on BWs. This method has high potential; however, an array of different antibodies is needed to screen for an array of different BWs. Currently this method is limited to a few biological threats and by false positive rates and high background levels due to antibody binding of non-specific and cross-reacting interferent materials.

Another detector alternative is ion mobility spectrometry (IMS). Though popular for explosives detection in airports and other venues, it is not a very specific detector and is prone to false positives in complex environments. IMS is a low resolution device. MS on the other hand has about 100x higher resolution, and QitTof MS can achieve an additional dimensionality of analysis by selectively fragmenting target ions to measure for known signature fragments (MS/MS). The general consensus is that IMS cannot achieve effective screening for a myriad of threats and maintain a low false positive rate. It is better suited for targeting one or a few threats at time.

High-Throughput Screening of CWs

Guarding the nation’s water supply requires fast-acting detection. Syagen has developed the most advanced, easy-to-operate detection systems for counterterrorism (chemical agents and explosives) and other applications requiring real-time, ultrasensitive chemical analysis of complex mixtures. Syagen’s Radiance Pro^® CW was designed for rapid monitoring of water supplies for the presence of chemical weapons and other potential terrorist threats. The system employs an autosampler and a photoionization (PI) source that enables reliable detection of targeted compounds in potentially complex mixtures. The mass analyzer is a quadrupole ion trap, time-of-flight (QitTof) system. The instrument is capable of MS/MS “on-the-fly” whereby the detection of a targeted mass can trigger an excitation waveform to provide a confirmatory fragment spectrum to identify the target compound. The entire instrument is transportable and occupies a 5 sq. ft. footprint.

Field-portable, high-performance screening

Syagen has taken the Radiance Pro technology and reduced it to a field portable version capable of direct analysis of air, liquid, and soil samples. Named the FieldMate, the monitor enables direct detection using photoionization. The FieldMate also has an optional electron ionization (EI) source for use with a GC front end. Like the Radiance Pro analyzer, the core field-portable MS system is also based on Syagen’s powerful QitTof MS technology. Syagen has also been developing a variation of the FieldMate for CB threat detection with the support of the DoD.

Applications

Syagen’s PI MS provides key advantages:

• Military force protection from threat of chemical/biological (CB) terrorism
  
  
• Chemical demilitarization and arms control treaty monitoring
  
  
• Emergency first response for hazardous materials
  
  
• Law enforcement forensics investigation
  
  
• Air quality monitoring for civilian defense and environmental pollution monitoring
  

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Product Data Sheets and Technology and Applications Data Sheets