Biological agent sensors

National Research Council, Sensor Systems for Biological Agent Attacks Protecting Buildings and Military Bases, Washington, D.C. The National Academies Press, 2005. 

In general, optical-based pH measurement techniques require relatively expensive and cumbersome instruments, and their sophisticated method cannot be easily carried out for routine assay. Interfering contact and reactions of the dye molecules, particularly considering in-vivo measurements, cannot be excluded [34], Some other possible factors, such as a weaker signal at shorter response times, complications in microfabrication, and difficulties in attaching the chemical or biological agents to the small fiber tip, are potential limitations for the application of these optical sensors to in-vivo measurements in micro environments [35]. 

Develop robust and reliable sensors for detection of chemical agents, biological agents, radioactive materials, and explosives. 

The threat described in the first part of this chapter spurred increased investment in research and development technologies to prevent, detect, and respond to terrorist attacks. One specific area of research, sensors, particularly for chemical and biological agents and radioactive materials, in addition to radar and sonar, is the subject of this book. After describing the threat, this chapter goes on to discuss the use of sensors, fielded sensor capabilities, and existing gaps in sensor capabilities. 

Chemical. Exquisitely sensitive chemical agent sensors are available, but work best under laboratory conditions. Environmental chemical sensors suffer many of the same issues as biological detectors. They lack sensitivity, are not sufficiently mobile or flexible, and require trained users. Several types of chemical detectors are in use and are mentioned above. 

Preparation of an environmental sample for delivery to the sensor and the sample cleanup afterwards are often the rate-limiting steps in the detection of biological agents, as well. Even for biodetection, sample preparation is a chemistry and materials science issue, currently accomplished using membranes and surface-active chemistries, binders, and ligands. Biological sample preparation remains an embryonic field. 

DNA base sensors for detection of biological agents have the advantages of high sensitivity, selectivity, ability to operate in turbid media, and to be amenable to miniaturization (Shah and Wilkins 2003). The biological agents include bacteria, viruses, and toxins that may be aerosoled deliberately in air, food, or water to spread terrorism and cause disease or death to humans, animals, or plants. 

The committee s assessment derives from the fact that the risk from asymmetric, or at least unconventional, attacks has increased. A determined adversary with even a small quantity of chemical or biological agent and a well-executed attack plan could produce significant consequences if supply chains, civilian support operations, and/or deployment schedules were disrupted. For example, the contamination of a ship in a foreign port raises the question as to how a captain should best utilize the non-medical science and technology at his disposal in response to an attack in which no sensor system allowed the avoidance of exposure. The extension of that question for the Non-Medical Science and Tech-... 

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