Selective, Specific, and Versatile Personal Biosensors to Organophosphate Chemical Toxins Composed of Polyurethane Immobilized Enzymes

Organophosphorus (OP) nerve agents are a serious threat to military and civilian personnel, so rapid detection of OP compounds in all of these forms is of paramount importance to prevent casualties. Recently, we combined porous polyurethane foam formed in situ from water-miscible hydrophilic urethane prepolymers and enzymes such as ChEs. One of the advantages of this technique imparted to the immobilized enzymes is resistance to denaturing events. Most important, the enzyme will not leach from the polyurethane support so the ChE-badge can now be used to sample for OPs in diverse environments such as soil and large bodies of water, as well as conventional sources such as air. In addition, immobilized enzyme badges are being designed with a unique attribute not present in the current nonimmobilized detectors: a rapid field system to identifying which OP is present. For instance, organophosphorus hydrolase (OPH) hydrolyzes sarin more readily than soman, while laccase hydrolyzes the VX agent preferentially over the G agent OPs. Currently, we are evaluating polyurethane immobilized laccase for long-term stability and kinetic properties of VX hydrolysis. Thus, the immobilized sensor can provide new features and testing of more diverse environments than the M256A1 and M272 kits combined. Also, the ability to identify the OP toxin in real-time using the immobilized differential detector would aid in treatment and securing the contaminated area, in the identification of the use of OPs, and permitting first responders to identify the OP present in a civilian terrorist act. †Telephone: 301 319 9987; fax: 301 319 9571 E-mail: [email protected] INTRODUCTION Traditional analysis of cholinesterase inhibitors is performed using gas and liquid chromatography and mass spectrometry (Witkiewicz, et al., 1990). These techniques have significant drawbacks when considering an individual kit for field deployment, including lack of portability, simplicity, cost, and rapid results. An alternate technology is a biosensor. Biosensors have been widely used to detect biological, pharmacological, or clinically Covalent ChE Incorporation at Aliphatic Amino Group(s) O (isocyanate) Report Documentation Page Form Approved OMB No. 0704-0188 Public reporting burden for the collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden, to Washington Headquarters Services, Directorate for Information Operations and Reports, 1215 Jefferson Davis Highway, Suite 1204, Arlington VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to a penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. 1. REPORT DATE 00 JAN 2002 2. REPORT TYPE N/A 3. DATES COVERED 4. TITLE AND SUBTITLE Selective, Specific, And Versatile Personal Biosensors To Organophosphate Chemical Toxins Composed Of Polyurethane Immobilized Enzymes 5a. CONTRACT NUMBER