Novel Aptamer:Peptide Based ECL Assays for Homeland Security

Accacia International LLC is a nascent biotech company, certified as a WBE/MBE, based in the heart of Texas and in the capital city of Austin. Accacia¿s scientists have provided consulting services and performed research work on SBIR projects in collaboration with other awardees, also developed products for commercial use. Accacia has also teamed up with the Ellington Labs at the University of Texas at Austin, to perform research work in the field of aptamer development. Accacia has to its credit several achievements. Although unrelated to this proposal since its inception in 2000, Accacia Inc. has developed and prototyped a reflectance IC Strip reader for the medical diagnostic industry. Patents are pending for the same. Additional patents are in process for two other technologies. Accacia undertakes OEM manufacturing of immunochromatographic strips for various diagnostic serum assays. Antibodies are often modified and conjugated for use in detection of biowarfare agents, foodborne pathogens, and for use in clinical diagnostics. Nucleic acids (aptamers) specifically selected to bind to targets of interest, have been demonstrated as potential replacement for antibodies due to their high specificity, accelerated development time, and low cost of production. Developments of aptamers to certain targets like Bacillus Anthracis (BA) whole spores also pose their own set of challenges. The chemistries available to aptamers are relatively limited and to some extent impede their ability to recognize an even wider variety of targets. For example, aptamers are by and large polyanions, and thus may have difficulty recognizing targets that are negatively charged. In order to expand the range of nucleic acid chemistry while still maintaining the inherent advantages of nucleic acid biosensors relative to antibodies, Accacia proposes to develop both covalent and non-covalent nucleic acid:peptide conjugates and to utilize these conjugates in novel signal transduction schemes. All of the molecular regents developed during Phase I will be adapted during Phase II for use with the IGEN ORIGEN analyzer. This analytical platform has been chosen for three reasons. First, electrochemical luminescence (ECL) provides extremely sensitive levels of detection when compared with traditional fluorescence detection systems. Second, ORIGEN technology is either currently being used, or soon to be employed by a number of government programs including the US Army Medical Research Institute of Infectious Diseases (USAMARID), the Department of Defense¿s Automated Biological Agent Testing System program (ABATS), the Department of Defense for the Joint Biological Agent Identification and Diagnostic System (JBAIDS) and the Department of Defense U.S. Army Space and Missile Defense Command. Third, there are numerous antibody assays on the ORIGEN which can be directly compared with the novel reagents we are generating, as per the requirements set out for the SBIR.