System and method for large scale detection of hazardous materials in the mail or in other objects

A system and method that enables early detection of hazardous materials, such as explosives and biological materials, in the early phases of mail handling or processing, is disclosed. The early detection of such hazardous material utilizing the system and method of this invention can be performed while the mail is being processed. The system includes at least two primary elements: an activation sub-system and a sense and analyze sub-system.

BACKGROUND OF THE INVENTION

This invention relates generally to the detection of hazardous material, and, more particularly to the application and sensing of sensitizing agents for early detection of potentially hazardous material associated with mail pieces or the delivery of other objects.

Recently there has been increased awareness of the potential for large-scale introduction of hazardous materials, that is, either explosives or biological organisms to create chaos or to harm an intended set of victims. Awareness to detection of explosives has led to development of reagents that can be used to detect the presence of nitroaromatics, organic nitrates, nitramines, inorganic nitrates, chlorates and bromates based explosives (see U.S. Pat. No. 5,480,612, “Kits for Detecting Explosives”, issued to Y. Margalit on Jan. 2, 1996).

Bacterial agents, such asBacillus anthracisandClosdistrium botilinum,can be used as biological hazardous materials. Detection methods for bacterial agents have been typically time-consuming using techniques such as florescent antibody staining (FAST) and enzyme linked immunoassay (ELISA). Detection systems have been recently disclosed that involve labeling antibodies with a detectable label where the detectable label utilizes fluorescence, chemiluminescence or chromatic change (see B. L. Mangold et al., international publication WO 01/83561 A2 for International Application No. PCT/US01/13648).

Detection methods have also been recently disclosed in the which the sensor is a polymer which has an alterable property, such as fluorescence or electrical conductivity, and the property is altered by a means of association of the polymer with a moiety including a property quenching element, a tethering element and a ligand or recognition element (see L. Chen et al., international publication WO00/66790 for International Application No. PCT/US00/12423 and see D. G. Whitten et al., international publication WO01/85997 A1 for International Application No. PCT/US01/14702). In this latter method, upon exposure to the biological agent, the agent can bind to the ligand or recognition element causing the moiety (with the bound biological agent) to separate from the polymer thereby un-quenching the alterable property. (The recognition element can be one of, but not restricted to, a chemical ligand, an antibody or antibody fragment, a peptide nucleic acid, or a protein.) Measurement of the alterable property results in detection of the biological agent.

A popular delivery method among the many delivery methods that terrorists or other criminals utilize to deliver such hazardous materials is to utilize the mail to deliver the hazardous material. In so doing, not only is damage incurred by the intended victims, but also by any set of potential victims that may be in a position of handling such objects as the mail during the delivery or distribution process.

As described above, there is currently technology available to law enforcement organizations to detect the presence of both explosive and biological threats. Test kits utilizing the above described materials generally require the gathering of a sample and analyzing offline. To date, however, there is a lack of systems for early detection of such hazardous material in the early phases of mail handling or processing. Systems currently in place do not deal with detection prior to entering into the formal distribution process. Thus, all along the distribution process potential nonintended victims are being subjected to hazardous material carried by, for example, letter or package mail.

There is a need for a system and method for early detection of such hazardous material in the early phases of mail handling or processing. There is also a need for a system and method for early detection of such hazardous material that can be performed while the mail is being processed.

BRIEF SUMMARY OF THE INVENTION

The system and method of this invention enable early detection of such hazardous material such as detection in the early phases of mail handling or processing. The early detection of such hazardous material utilizing the system and method of this invention can be performed while the mail is being processed.

The system of this invention includes two primary elements: an activation sub-system and a sense and analyze sub-system. The sense and analyze sub-system performs the following major functions: illumination and sensing and analysis of the activation results. In one embodiment, the activation sub-system includes a dispensing system and control of the dispensing system by the computer system. In that embodiment, the illumination and sensing functions are performed by at least one radiation source and at least one detector. During operation of the above embodiment of the system of this invention, a mail piece is transported on a conveyor belt and is placed in the region where the dispensing system can deposit sensitizing agents on the mail piece. After deposition of the sensitizing agents on the mail piece, the radiation source illuminates the mail piece. The interaction of the radiation source with the sensitizing agent is detected by the detector. The output of detector is provided to a computer system where computer readable code causes a processor to analyze the detector output obtained from the interaction of the output of the radiation source and the sensitizing agent deposited on the mail piece. If the analysis indicates that the mail piece possibly contains hazardous materials, the computer readable code causes the processor to identify the mail piece as potentially hazardous. The mail piece can then be set aside for further testing.

For a better understanding of the present invention, together with other and further objects thereof, reference is made to the accompanying drawings and detailed description and its scope will be pointed out in the appended claims.

DETAILED DESCRIPTION OF THE INVENTION

A system and method for early detection of such hazardous material in the early phases of mail or delivery package handling or processing are disclosed herein below. The early detection of such hazardous material utilizing the system and method of this invention can be performed while the mail or similar delivered object is being processed.

Although the description below is given in reference to a mail piece, the term “mail piece” as used herein refers to any object in a delivery system. For example, the same description of this invention applies to a package in a delivery system, packages being loaded onto a transport system and other situations where a package would be handled and transported.

A block diagram of an embodiment of the system of this invention is shown inFIG. 1and a schematic, block representation of an embodiment of the system of this invention is shown inFIG. 2.

Referring toFIGS. 1 and 2, the system110of this invention includes two primary elements: an activation sub-system85and a sense and analyze sub-system100. The sense and analyze sub-system100includes two components: an illumination and sensing component90and an activation results analysis component95. In the embodiment shown inFIG. 2, the activation sub-system85ofFIG. 1includes the dispensing system125and the control of the dispensing system125by means of computer readable code in memory220executing in processor210of computer system120. In this embodiment, the illumination and sensing component90includes at least one radiation source105and at least one detector115. The radiation source105is controlled by computer120and the detector115provides its output to computer120. The computer120has, in memory220, computer readable code that causes processor210to control the receiving of the output of the detector115and to analyze the output of detector115when activated mail piece10is illuminated by a radiation source105. The computer120also has, in memory220, computer readable code that causes processor210to control the radiation source105and the dispensing system125.

The operation of the above embodiment of the system of this invention can be best described in reference toFIGS. 2 and 3. Mail piece10is transported on conveyor belt150, or a similar mail transport system, and is placed in the region where dispensing system125can deposit sensitizing agents on mail piece10. For mail processing systems, the transport could be one of several existing transports, for example, the Delivery Bar Code Sorter or Automated Flats Sorting Machine. Transport systems, such as conveyor belts and equivalent transport systems, are known in the art. As the mail piece10approaches the dispensing system125, in one embodiment, a location sensing and control system122, such as one of the vision systems known in the industrial art, would determine the location and size of the mail piece10. The location and size information is provided to computer120and stored in memory220. In one embodiment, computer120has, in memory220, computer readable code for receiving the output of the location sensing and control system and for causing the processor210to determine the location and size of the mail piece10.

Dispensing system125can have a variety of means for depositing the sensitizing agents. The means required are determined by the medium that carries the sensitizing agent. For example, if the sensitizing agent is one of the reagents described in U.S. Pat. No. 5,480,612, which is incorporated by reference herein, Reagents A, B, and C, described therein, could be deposited using a spray system, a drop dispensing system or an ink jet type nozzle and plunger system. All the above systems can be controlled so that the deposition occurs at a given time and at a desired range or loci of positions. (Known techniques, such as computer vision or digital imaging, use of fiduciary marks, and closed loop control systems can be used to control the deposition.) Control of the dispensing system125, in one embodiment, occurs via the processor210in computer120operating under computer code embodied in memory220. Deposition of Reagent D of U.S. Pat. No. 5,480,612 requires consideration of the acidity of the reagent. (Reagent A of U.S. Pat. No. 5,480,612 is an sensitizing agent for the detection of nitroaromatics such as TNT; reagent B serves the same function for organic esters of nitric acid and nitramines, reagent C serves the same function for inorganic nitrates and reagent D for chlorates or bromates.) Similarly, if the molecules described in international publication WO00/66790 for International Application No. PCT/US00/12423, in international publication WO01/85997 A1 for International Application No. PCT/US01/14702, or in international publication WO01/66721 A2 for International Application No. PCT/US01/07163 (N. Usman et al.) are used in the sensitizing agents, the molecules can be contained in a water-based, a water/DMSO based solution, a gel or clay base. These solutions could be deposited using a spray system, a drop dispensing system or an ink jet type nozzle and plunger system. The clay based or gel based mixtures could be deposited using a wide nozzle and plunger system. In one embodiment, after deposition, the mail piece10would appear as shown inFIG. 4, where stripes310,320are obtained by depositing sensitizing agents for the detection of explosives (such as reagents A, B, C, D of U.S. Pat. No. 5,480,612) and stripes330,340,350are obtained by depositing sensitizing agents for the detection of biological agents (such as solutions or suspensions of the molecules described in international publication WO00/66790, international publication WO01/85997 or international publication WO01/85997 A1).

After deposition, as the mail piece travels along on conveyor belt150and, after a travel time equal to or greater than the longest activation latency time for the deposited sensitizing agents has elapsed, the sensitized mail piece10approaches illumination and sensing component90. The speed of the conveyor belt could require modulation or adjustment to accommodate the latency time. As the mail piece10approaches the illumination and sensing component90, in one embodiment, the location sensing and control system122, such as one of the vision systems known in the industrial art, would determine the location of the mail piece10and the location of stripes310,320,330,340,350, if necessary.

Still referring toFIG. 2, radiation source105, under control of computer120, illuminates the mail piece10. It should be noted that radiation source105can be more than one radiation source and that the radiation source105could include, in one embodiment, an optical subsystem (not shown) to focus the beam of radiation. The radiation source105emits the radiation in the wavelength range required to activate one of the sensitizing agents deposited by dispensing system125. In the embodiment in which one of the sensitizing agents is one of the reagents described in U.S. Pat. No. 5,480,612, the required radiation source for that sensitizing agent could be ambient light or a “white” light source. In the embodiment in which one of the sensitizing agents is one of the solutions or suspensions of the molecules described in international publication WO00/66790, international publication WO01/85997 or international publication WO01/85997 A1, where the molecules are designed to detect a biological agent by a change in fluorescence or luminescence, the required radiation source for that sensitizing agent would be a radiation source of a determined wavelength spectrum. The radiation source105, in that embodiment, would be a laser or a filtered broad wavelength source and, if needed for sensitivity or to avoid interaction with other sensitizing agents, it would be focused by an optical system (not shown). It should be noted that it is possible to select other alterable properties besides those discussed above. The alterable property can also be, but is not limited to, a change in UV absorbance, optical rotation, capacitance, or resistance (see, for example, international publication WO01/66721 A2). The latter alterable properties require different “radiation” sources. Sensing of UV absorbance would require a UV source; sensing of optical rotation would require a radiation source of a predetermined wavelength and polarization; sensing of capacitance or resistance would require a source of radio frequency (RF) radiation.

The interaction of the radiation source105with the sensitizing agent in one of the “stripes”310,320,330,340, or350is detected by detector115. In the embodiment in which one of the sensitizing agents is one of the reagents described in U.S. Pat. No. 5,480,612 and the source of radiation105is ambient light or a “white” light source, detector115can be one or more CCD or CMOS detectors with color filters. The reagents described in U.S. Pat. No. 5,480,612 exhibit a change in color when exposed to a target explosive material. A CCD or CMOS detector with color filters would enable calorimetric detection. In the embodiment in which one of the sensitizing agents is one of the solutions or suspensions of molecules designed to detect a biological agent by a change in fluorescence or luminescence, and the radiation source105is laser or a filtered broad wavelength source, detector115can be one of the detectors described in E. L. Dereniak, D. G. Crowe,Optical Radiation Detectors,ISBN 0-471-89797-3 (1984, John Wiley & Sons). The detector115, in this embodiment, includes means for detecting the emitted radiation in a predetermined wavelength band (spectral band). Examples of such means (also referred to as wavelength separating means) are filters, including Liquid Crystal Tunable Filters (LCTF) or Acousto-optic Tunable Filters (AOTF) or a holographic grating or a prism or a polychromator, placed between the emitting mail piece10and the photo-detecting component of detector110. Collecting optics could be used between the wavelength separating means and the emitting surface. If the alterable property of the sensitizing agent is the UV absorbance, optical rotation, capacitance, or resistance, detector115would be a UV detector, a polarization sensitive optical detector, or an RF detector or antenna, respectively.

The output of detector115is provided to computer system120. Memory220, a computer usable medium, has computer readable code embodied therein that causes processor210to analyze the detector output obtained from the interaction of the output of source105and the sensitizing agent deposited on mail piece10. If the analysis indicates that mail piece10appears to contain hazardous materials, the computer readable code causes processor210to identify the mail piece10as potentially hazardous. The identification can occur through an output device (not shown) such as a video display unit, a printer or an alarm or a combination of these output devices. In one embodiment, if the analysis indicates that mail piece10potentially contains hazardous materials, the computer readable code causes processor210to send signals to actuator control module230. Actuator control module230causes actuator140to select mail piece10, separate it from the stream of mail pieces and set it aside in area160for further inspection.

It should be noted that, although the above discussion of an embodiment of this invention describes the operation of the embodiment with a radiation source105and a detector115, several radiation sources and several detectors would be used to analyze the response of several sensitizing agents for the detection of different hazardous materials.

It should also be noted that the term “mail piece” as used herein refers to any object in a delivery system. The term “radiation source” as used herein applies to any source that provides an output that interacts with a sensitizing agent. “Luminescence” as used herein includes fluorescence.

Each computer readable code within the scope of the claims below may be implemented in any programming language, such as assembly language, machine language, a high-level procedural programming language, or an object-oriented programming language. The programming language may be a compiled or interpreted programming language.

Each computer readable code may be implemented in a computer program product tangibly embodied in a computer-readable storage device for execution by a computer processor. Method steps of the invention may be performed by a computer processor executing a program tangibly embodied on a computer-readable medium to perform functions of the invention by operating on input and generating output.

Common forms of computer-readable or usable media include, for example, a floppy disk, a flexible disk, hard disk, magnetic tape, or any other magnetic medium, a CDROM, any other optical medium, punched cards, paper tape, any other physical medium with patterns of holes, a RAM, a PROM, and EPROM, a FLASH-EPROM, any other memory chip or cartridge, a carrier wave, or any other medium from which a computer can read.