Submission of proposals
Edgewood Chemical Biological Center (ECBC)
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| Edgewood Chemical Biological Center (ECBC)
A00-145 TITLE: Nontoxic Biodegradable Nanomaterials and Biomaterials Signature Reduction TECHNOLOGY AREAS: Materials/Processes OBJECTIVE: Develop nontoxic nanomaterials and/or biologically derived nontoxic fibers that can be used as aerosols to attenuate electromagnetic radiation. DESCRIPTION: High aspect ratio fibers and flakes composed of electrically conductive materials are known to attenuate electromagnetic radiation in the millimeter and infrared regions of the spectrum, respectively. Examples include conductive metal flakes for IR screening, conductive carbon fibers or metal coated fiberglass chaff for millimeter screening, and submicron diameter conductive filaments or whiskers for broadband screening. In the first and last of these examples increased screening efficiency is generally associated with increased aspect ratio (i.e. very thin flakes and very long fibers). Aerosolization of these materials produces an obscurant cloud, or "smoke screen" that can protect warfighters from weapon systems based on electromagnetic sensors. (See Optical Engineering 22(1)071-077, 1983.) Often incorporation of the same particles in films and coatings can provide a low observable effect, reducing the target signature of assets to protect them from threat sensors. Current obscurant materials suffer from high cost, inhalation toxicity, environmental impact and non-optimal performance. Recent advances in nanotechnology, biotechnology and genetic engineering, particularly in the areas of biotics, biomimetics, and self-structuring materials provide new opportunities for the design and manufacture of optimized obscurant materials. A major contribution to the figure of merit for smoke materials is mass extinction coefficient at the wavelength(s) of interest. The goal of this topic is to reach extinction coefficients exceeding 4m2/g . The advantages of biologically derived materials are particularly noteworthy from the standpoint of toxicology and environmental impact. Biological materials are also of significant interest because of the well-controlled uniformity between particles, the possibility of product tailoring via bioengineering and the potential for manufacture via bioprocessing. In use these materials would be aerosolized via munitions, pyrotechnics, or smoke generators. Volume, weight and attainable dissemination efficiency are important considerations and a system which takes advantage of atmospheric materials is a significant bonus. An example of taking advantage of atmospheric materials is the phosphorous smokes, in which dispersed phosphorous reacts with atmospheric constituents to yield, by weight, more screening material than was carried to the battlefield. PHASE I: Demonstrate the technology for manufacturing materials with appropriate physical parameters and conduct initial dissemination and attenuation screens. Identify general toxicity and environmental effects. The deliverables for Phase I will be a report on the manufacture process and materials characteristics, including the potential for parametric control of particle morphology, and small (0.5 gm or 1cc) quantities of the materials for evaluation. PHASE II: Optimize material based on attenuation, toxicity, environmental compatibility and price. Scale-up to production of kilogram quantities of optimized material. Forecast ultimate manufacture costs. Deliverables for Phase II will be a comprehensive final report and kilogram quantities of optimized materials. PHASE III DUAL USE APPLICATIONS: Phase III will involve final optimization, testing, scale-up and packaging. Dual use will include low observable and stealth applications, primarily of a military nature. In the commercial sector applications will include powder manufacturing applications, such as powder metallurgy and nanocrystalline ceramics, in which nanoparticulate precursors provide valuable controls over product characteristics. There is potential for application in the microelectronic field where nanowires are critical to the continuing miniaturization of components. OPERATING AND SUPPORT COST (OSCR) REDUCTION: Reducing cost, improving performance, eliminating toxicity and reducing environmental impact will provide significant reductions in the cost of battlefield operation by requiring less material, less expensive material, and fewer logistic expenses associated with smoke operations. Resultant increased survivability of assets provide additional savings. Success in this project will provide operational capabilities that are safe and cost effective as training materials as well, eliminating the need for smoke items that are specific to training purposes and realizing associated cost reductions. Similar cost reductions can be expected from the applications of this technology to signal reducing coatings. KEYWORDS: biomaterials, fibers, biotics, obscurants, nanomaterials, nanofibers, nanowhiskers, obscurants A00-146 TITLE: Stabilization of Enzymes for the Destruction of Toxic Materials and Chemical Agents TECHNOLOGY AREAS: Materials/Processes OBJECTIVE: To develop methods for the protection and stabilization of enzymes, which can be used to degrade toxic materials and chemical threat agents or in detection of toxic materials. DESCRIPTION: The potential utility of enzymes and biocatalysis in the detoxification of contaminated surfaces and toxic spills is widely accepted.1,2 Several factors limit the practicality of the broad employment of enzymes as decontaminants or in detectors. The acute sensitivity of enzymes to environmental conditions is the foremost shortcoming. The development of a mechanism to protect and stabilize enzymes from adverse conditions is desired. Relevant environmental factors detrimental to enzyme systems include enzyme oxidation and alkylation as well as deviations from optimal pH conditions for enzyme activity. Numerous enzymes having catalytic activity on chemical warfare agents (G-series and V-series agents) have been isolated. The susceptibility of enzymes to alkylation by mustards or other alkylating agents critically limits their practical utility as decontaminants or as a means of protection from chemical warfare agents. Mustards are reported to react with many functionalities within proteins, including carboxyl, thiomethyl, sulfhydryl, and amino groups depending upon environmental conditions such as pH or temperature.3 These modifications cause numerous changes in a protein's physico-chemical properties including increased sulfur content, altered isoelectric points, and enhanced susceptibility to denaturation. Specifically the catalytic activity and substrate specificity of enzymes needs be retained in the presence of mustard type alkylating agents and oxidizing bleaches. Oxidative solutions such as traditional decontaminants including hypochlorite bleaches and emulsions are commonly used to detoxify surfaces.4,5 Enzymes may be used with oxidative solutions for the degradation of agents that are not enzyme substrates. Unfortunately many enzymes are susceptible to oxidation and are denatured in the presence of bleaches. The goal of this work would be to develop methods using approaches such as PEGylation, protein cross-linking or nanoencapsulation for the protection and stabilization of enzymes being used for destruction of toxic materials and threat agents. PHASE I: Design a protection vehicle for enzymes known to have potential utility in decontamination. The proposed research must address a). resistance to pre-incubation with and exposure to mustard and other alkylating agents while defining limitations with respect to mustard concentration and exposure time, b). feasibility of incorporating enzymes within oxidative solutions for the decontamination of toxic materials, and c). broadening the pH range acceptable for enzyme catalysis. PHASE II: Assess the performance of the stabilized enzymes on chemical warfare grade agents including Sarin, Soman, Tabun, and VX in the presence of Mustard (HD). This phase requires implementing live agent testing. PHASE III DUAL USE APPLICATIONS: Phase III includes identification and development of conditions for utilization of the protected enzyme systems with current reactive chemistries. The catalytic activity and substrate selectivity of enzymes make them interesting catalysts for a broad variety of industrial and commercial processes. An effective means of minimizing protein denaturation due to chemical modification via oxidation and alkylation or due to extremes in pH would have far-reaching implications. Organophosphorus compounds are generated in substantial quantities in the private sector and have lead to the contamination of ground water from organophosphorus pesticides or waste streams generated by industry. The similarity of chemical agents to commercially important organophosphorus products means that the techniques developed in this topic are directly applicable to industry. The modified enzymes would be commercially relevant to the destruction of organophosphorus pesticides and using enzymes in organic synthesis because of their enantiomeric selectivity. OPERATING AND SUPPORT COST (OSCR) REDUCTION: Current decontamination systems utilize rather hazardous reactive solutions (DS2) which require a significant cost in transport, maintenance, and storage. Enzyme-based systems would consist primarily of dry powders which would be added to available water or water-based liquids in the field. Since they will have long storage life without special handling, it will greatly reduce storage, maintenance and transportation costs. Since they would be inherently less hazardous operational expenses would also be reduced. REFERENCES: Longwell, P. (Chairman) National Research Council Commission on Engineering and Technical Systems. 1993. Alternative technologies for the destruction of chemical agents and munitions. 2101 Constitutions Ave., Washington, DC. 1. (a) Cheng, T.-c., Rastogi, V.K., DeFrank, J.J., and Sawaris, G.P., 1998, "G-type Nerve Agent Decontamination by Alteromonas prolidase", Annals of the New York Academy of Sciences, 864, 253-258; (b) K.E. LeJeune, J.R. Wild, and A.J. Russell, 1998, "Nerve Agents Degraded by Enzymatic Foams", Nature, 395, 27-28; and (c) K.E. LeJeune and A.J. Russell, 1999, "Biocatalytic Nerve Agent Detoxification in Fire Fighting Foams" Biotechnology and Bioengineering, 62, 659-665. 2. Papirmeister, B. et al., Medical Defense Against Mustard Gas (1991) CRC Press, Inc. p. 111-114. 3. Yu-Chu Yang, James A. Baker, and J. Richard Ward, 1992, "Decontamination of Chemical Warfare Agents", Chem. Rev., 92, 1729-1743. 4. Yu-Chu Yang, 1999, "Chemical Detoxification of Nerve Agent VX" Acc.Chem.Res. 32, 109-115.
A00-147 TITLE: Compact, Lightweight, Modular Infrared Spectroscope For Chemical And Biological Agent Detection TECHNOLOGY AREAS: Materials/Processes Objective: Develop a compact infrared spectrometer that can be used for point and standoff chemical and biological detection Description: Advanced warning of the presence of chemical and biological materials may be monitored spectroscopically using instruments that operate in the infrared region. However, currently fielded sensors that take advantage of the infrared spectral signatures of chemical agents to effect detection are heavy, bulky, and expensive. Compact, lightweight sensors are fielded, but these are point samplers that must be in the presence of the agent in order to effect detection and warning. Recent advances in materials science and technology present opportunities for the design and construction of a modular, compact spectrometer that can perform both functions - point sensing and remote sensing - alleviating the need for two or more types of sensors in the inventory. The sensor may either employ a local source and multipass cell for point sensing, or switch to passive remote sensing employing collection optics. Alternatively, a small, unmanned aerial vehicle may be employed to transport the sensor in point sensing configuration to probe the atmosphere for contamination. PHASE I: Demonstrate the technology and design and model a proposed spectrometer. Model the ability of the spectrometer to record infrared spectra of gases and aerosols using both a local sampler including, for example, a source and detector, and using an optical interface for passive remote sensing, such as an infrared telescope. The deliverable from phase I will be a report of the proposed design of the spectrometer and a validation of the principle of operation in the form of actual experimental data and system performance modeling. PHASE II: Construct and test the hardware platform, and develop the construction and component selection so as to propose a means of large-scale manufacture of inexpensive multiple modular sensors. Develop algorithms for detection of chemical and biological agents with the spectrometer in both point and standoff modes of operation. PHASE III DUAL USE APPLICATIONS: In the operational military setting, the end state should be a competitive device capable of autonomous monitoring for chemical and biological agents in a modular system, easily converted to either point or remote sensing operation with minimal operator knowledge and training. This device would be of immediate value to the chemical industry for process monitoring, to educational institutions looking for low-cost spectrometers for programs in chemistry and remote sensing, and to a number of government and state agencies and emergency with a requirement for a compact field spectrometer for chemical identification. OPERATING AND SUPPORT COST REDUCTION (OSCR): By replacing several types of devices currently in the chemical detection inventory with a single modular, convertible sensor, the innovative compact infrared spectrometer would reduce costs involved in outfitting troops with both remote and point detection and alarm systems for chemical and biological agents. REFERENCES: Hoffland, L.D., Piffath, R.J., and Bouck, J.B. "Spectral signatures of chemical agents and simulants," Opt. Eng, 24, 982 (1985); Naumann, D., Schultz, C.P., and Helm, D. "What can infrared spectroscopy tell us about the structure and composition of bacterial cells?" in Infrared Spectroscopy of Biomolecules, H.H. Mantsch and D. Chapman, eds., Wiley-Liss, New York, 1996. KEYWORDS: Chemical and Biological detectors, Chemical and Biological agents, infrared spectrometry, IR spectrometer. Download 1.22 Mb. Share with your friends:
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