Field Demonstration and Method Validation of NRL Environmental Immunosensors
Abstract
To meet environmental remediation goals, there is a need for rapid, quantitative detection of hazardous pollutants such as explosives. Biosensors provide a rapid, specific, sensitive, portable, and inexpensive means to fulfill those needs. The Naval Research Laboratory has developed two methods for measuring TNT and RDX. These methods employ either the Analyte 2000 or the FAST 2000 optical instruments, both engineered by Research International (Woodinville WA) in collaboration with NRL. These biosensors, based on fluorescence immunoassay techniques, are interfaced to portable computers for instrument control and data analysis. Both biosensors are portable, and easily set-up within 30 minutes on a small table. The Analyte 2000 is a fiber optic biosensor capable of simultaneously monitoring four optical probes. It is based on a competitive fluoroimmunoassay, in which a fluorescent molecule, similar to the analyte, competes with the analyte for binding sites on antibodies immobilized on the surface of an optical probe. In this format, the fluorescence signal is inversely proportional to the amount of analyte in the sample. Results are determined in 12-17 minutes depending on the analyte. Multiple analyses are performed on the same fiber probe to reducing probe to probe variation issues for quantitation. The Fast 2000 is a continuous flow immunosensor based on a displacement immunoassay, with the key components being antibodies specific for the analyte immobilized on a membrane support, fluorescent signal molecules similar to the analyte saturated on the immobilized antibodies, and a fluorescent detector. Upon injection of an explosive contaminated sample, fluorescent signal molecules are released into the flow stream and detected by a detector. The FAST 2000 quantitates samples with minimal sample preparation and reagent addition. Analysis is complete within five minutes, with the fluorescent signal being proportional to the analyte concentration in the sample.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 07, 2000
- Accession Number
- ADA608314
Entities
People
- Anne Kusterbeck
- Lisa C Shriver-Lake
Organizations
- United States Naval Research Laboratory