Development of Biological Obscurants

The DoD has funded a number of nanotechnology based obscurant projects. Recent studies have shown the potential health and environmental risk associated with nanoparticle exposures. Development of biologically based obscurants could eliminate these shortcomings by providing multi-spectral capabilities, environmental-friendly (i.e., biodegradable), non-pathogenic constituents and non-toxic by-products. GXI and Dr. James P. Chambers of the University of Texas at San Antonio propose to develop biological obscurants for battlefield applications based on the use of bacteriochlorophylls. In Phase I, GXI and Dr. Chambers will conduct spectroscopic investigations of bacteria containing bacteriochlorophyll b with tetrapyrrole pigments to demonstrate the feasibility of using chlorophyll compounds as obscurants. We will also investigate the use of combinatorial techniques to alter the protein microenvironment near the tetrapyrrole ring and thus tune the absorption spectra to provide multi-spectral capabilities. The rational for use of chlorophyll compounds as an obscurant is based on the broad range of spectral absorption using chlorophyll derivatives. Absorption peaks coincide well with specific areas of military interest including: (1) the visible range; (2) night vision ranges of 700 to 800 and 900 nm for 3rd generation imaging technology; and (3) the 1064 nm range for most smart bomb and missile laser guidance systems.