| || Biological Warfare Agents
Author : Kamboj, Dev Vrat ;Goel, Ajay Kumar;Singh, Lokendra
Source : Defence Science Journal ; Vol:56(4) ; 2006 ; pp 495-506
Subject : 57.089 Biomedical Sciences ;623.459 Chemical Weapons
Keywords : Biological warfare agents;Biological warfare;Weapons of mass destruction;BTWC;Biological and Toxin Weapons Convention;Biodefence;Bacterial agents;Viral agents;Toxins
Abstract : There is a long historic record of use of biological warfare (BW) agents by warring countries against their enemies. However, the frequency of their use has increased since the beginning of the twentieth century. World war I witnessed the use of anthrax agent against human beings and animals by Germans, followed by large-scale field trials by Japanese against war prisoners and Chinese population during world war II. Ironically, research and development in biological warfare agents increased tremendously after the Geneva Protocol, signed in 1925, because of its drawbacks which were overcome by Biological and Toxin Weapons Convention (BTWC) in 1972. Biological warfare programme took back seat after the 1972 convention but biological agents regained their importance after the bioterrorist attacks of anthrax powder in 2001. In the light of these attacks, many of which turned out to be hoax, general awareness is required about biological warfare agents that can be used against them. This review has been written highlighting important biological warfare agents, diseases caused by them, possible therapies and other protection measures.
| || Nanoparticle-based Sensors
Author : Khanna, V.K.
Source : Defence Science Journal ; Vol:58(5) ; 2008 ; pp 608-616
Keywords : Nanoparticles;Nanomaterials;Chemical warfare;Biological warfare;Toxins;Sensors;Biosensors;Quantum dots;Chemiresistors
Abstract : Nanoparticles exhibit several unique properties that can be applied to develop chemical and biosensors possessing desirable features like enhanced sensitivity and lower detection limits. Gold nanoparticles are coated with sugars tailored to recognise different biological substances. When mixed with a weak solution of the sugar-coated nanoparticles, the target substance, e.g., ricin or E.coli, attaches to the sugar, thereby altering its properties and changing the colour. Spores of bacterium labeled with carbon dots have been found to glow upon illumination when viewed with a confocal microscope. Enzyme/nanoparticle-based optical sensors for the detection of organophosphate (OP) compounds employ nanoparticle-modified fluorescence of an inhibitor of the enzyme to generate the signal for the OP compound detection. Nanoparticles shaped as nanoprisms, built of silver atoms, appear red on exposure to light. These nanoparticles are used as diagnostic labels that glow when target DNA, e.g., those of anthrax or HIV, are present. Of great importance are tools like gold nanoparticle-enhanced surface-plasmon resonance sensor and silver nanoparticle surface-enhanced portable Raman integrated tunable sensor. Nanoparticle metal oxide chemiresistors using micro electro mechanical system hotplate are very promising devices for toxic gas sensing. Chemiresistors comprising thin films of nanogold particles, encapsulated in monomolecular layers of functionalised alkanethiols, deposited on interdigitated microelectrodes, show resistance changes through reversible absorption of vapours of harmful gases. This paper reviews the state-of-the-art sensors for chemical and biological terror agents, indicates their capabilities and applications, and presents the future scope of these devices.