We report the use of carbon nanotubes as a sensor for chemical nerve agents. Thin-film transistors constructed from random networks of single-walled carbon nanotubes were used to detect dimethyl methylphosphonate ~DMMP!, a simulant for the nerve agent sarin. These sensors are reversible and capable of detecting DMMP at sub-ppb concentration levels, and they are intrinsically selective against i...

Synthesis of chimeric 9-mer oligonucleotides containing methylphosphonate-linkages and locked nucleic acid (LNA) monomers, their binding affinity towards complementary DNA and RNA, and their 3'-exonucleolytic stability are described. The obtained methylphosphonate-DNA/LNA chimeric oligonucleotides display similarly high RNA affinity and RNA selectivity as a corresponding 9-mer DNA/LNA chimeric ...

The use of activated carbon fabrics (ACFs) that are desorbed electrothermally, also known as the Joule effect, is explored as a potential method to create a regenerating chemical warfare agent (CWA) filter. Electrical resistance vs. temperature measurements are presented for KynolTM-based ACF and compared with results for ACFs produced from other substrates. Adsorption and desorption results fo...

Chemical warfare agents (CWA) continue to present a threat to civilian populations and military personnel in operational areas all over the world. Reliable measurements of CWAs are critical to contamination detection, avoidance, and remediation. The current deployed systems in United States and foreign militaries, as well as those in the private sector offer accurate detection of CWAs, but are ...

Ab initio quantum chemical calculations have been performed to study the adsorption of trichlorophosphate, dimethyl methylphosphonate, and Sarin via hydrogen bonding to Si-OH groups on the amorphous SiO2 (a-SiO2) surface. Two SiO2 models are used: a small Si5O7H8 “cagelike” cluster and a larger Si21O56H28 structure designed to approximate the local environment in a-SiO2. In the latter case, reg...

Organophosphates are powerful inhibitors of acetylcholinesterase, which is critical to nerve function. Despite continuous research for detecting the highly toxic organophosphates, a new and improved methodology is still needed. Herein we demonstrate simple-to-fabricate chemiresistive gas sensors using conducting-polymer polypyrrole (PPy) nanotube transducers, which are chemically specific and c...

Interactions of nerve G-agents (sarin and soman) and their simulants DMMP (dimethyl methylphosphonate) and DIFP (diisopropyl fluorophosphate) with water and components of polyelectrolyte membranes are studied using ab initio calculations in conjunction with thermodynamic modeling using the conductor-like screening model for real solvents (COSMO-RS). To test reliability of COSMO-RS calculations,...

From literature data on partition coefficients and in some cases solubilities in nonaqueous solvents we have been able to determine Abraham descriptors for several series of organophosphorus compounds including the dialkyl- and diaryl-phosphates (dialkylphosphoric acids), trialkyl- and triphenyl-phosphates, dialkylphosphinic acids and diphenylphosphinic acid, trialkyl- and triaryl-phosphine oxi...