Reversible Fiber Optic Biosensor for Detection of Explosives

Period of Performance: 09/10/1998 - 09/14/1999


Phase 2 STTR

Recipient Firm

Physical Optics Corp.
1845 West 205th Street Array
Torrance, CA 90501
Firm POC
Principal Investigator

Research Institution

University of New Mexico
EECE MSC01 1100 1 University of New Mexico
Albuquerque, NM 87131
Institution POC


A fiber optic immunosensor system for detection of multiple explosives constituents is proposed, based on neural network evaluation of a sensor array's response. The system incorporates a novel concept for the realization of a fully reversible immunosensor, in which an analog, a competing agent for binding to the antibody, is fluorescently labeled and bound to the surface together with the immunochemistry. This method eliminates the need for constant replenishment of fluids, and makes the system intrinsically reversible. Additionally, this method enables compact multi-analyte sensor arrays, since the sensing fields do not require treatment with individual chemical agents. The chemical constituents for this sensor were successfully synthesized and tested in Phase I. The detection chemistry interacts optically with an optical fiber, as part of a compact fiber optic system. Short-period fiber Bragg gratings, whose fabrication was demonstrated in Phase I, will be used for spectral source filtering and suppression of excitation light. Implementation of the complete system in fiber optics allows multi-analyte sensing, and reduces system size and weight. The pattern recognition mechanism uses responses of sensing fields highly specific to an analyte, and fields of broader affinity range, to identify and quantify even minute traces of explosives. BENEFITS: Besides the intended use for mine sweeping, the system will immediately have great potential for explosive detection in airports and other potential targets for terrorism. The fiber optic design also makes the system well suited for distributed sensing over large areas. The novel immunosensor concept can be adapted to a large number of different target substances.