RFID Biosensors for the Detection of IEDs at 400 m Stand-off Distance Dr. William D. Hunt School of Electrical and Computer Engineering Georgia Institute of Technology Atlanta, GA and Dr. Peter J. Edmonson P.J. Edmonson Ltd. Hamilton, Ontario

Outline Team background Technology background Current RFID/Biosensor Current 2D and 3D Algorithms Myths and Truths Proposed IED Detection Solution Proposed RFID/Biosensor

Team Background (Hunt) Research Focus: Microelectronic Acoustic devices and their application to molecular recognition in liquid and vapor phase Jointly appointed at Emory University Medical School and Georgia Tech 25 years experience with acoustic wave devices. 6 years experience with biosensors Fully equipped R&D lab for device design, fabrication and testing 70 publications in refereed journals and conference publications 10 patents (provisional and full)

Team Background (Edmonson) 33 years experience with acoustic wave devices. > 40 Patents granted and several pending in radio, acoustic wave devices, RFID and Biosensors. First RF engineer (1994) at Research in Motion, co-developed the Blackberry. Part owner of RF/electronics design and manufacturing facilities (Toronto/Atlanta).

Experimental Setup For Lab Experiments Conducted to Date Target: C-4 (RDX), TNT Ref. Anti-RDX Anti-TNT Emission Sensor array Flowcell Intake Sensor 1: reference Sensor 2: anti-RDX Sensor 3: anti-TNT 5um filter inserted before the inlet to ensure no particle uptake

Technology Background Successful detection of low-vapor pressure substances i.e. TNT, RDX, PETN, AN (Ammonium Nitrate) and Cocaine using acoustic wave biosensors. Able to discriminate against close chemical analogs such as musk oil. Current longevity of antibodies ≈ 2 weeks

Technology Background (2) Development of 2D and 3D detection algorithms. Presently involved in aptamer, peptide, antibody and plasma-deposited hydrogels research. Currently developing an RFID/Biosensor.

Technology Background (3) RFID/Biosensor An interrogation unit transmits an RF signal to an RFID/Biosensor. RFID/Biosensor returns a modified signal indicative of cumulative binding events. A 2.45 GHz RFID/Biosensor fabricated on quartz.

Technology Background (4) Algorithm Development 2 selected antibodies Detection with a 2D Map Only 10 samples required.

Technology Background (5) Algorithm Development 3 selected antibodies Detection with a 3D Map Only 10 samples required.

Myths and Truths Myth: Antibodies must be designed for a specific substance. Truth: No, within analogous groups such as explosives similar molecule binding due to the promiscuity of the antibody can take place.

Vapor Pressures for selected low vapor pressure chemicals Myths and Truths (2) Myth: Explosives have too low a vapor pressure to ever be detected directly so one must use particle collection prior to detection Truth: We have detected cocaine, RDX and TNT in the vapor phase from dry samples. 10-9 Torr 10-8 Torr 10-7 Torr 10-6 Torr 10-5 Torr RDX PETN Cocaine TNT Vapor Pressures for selected low vapor pressure chemicals

Our Proposed IED Detection Solution During a period of hours or days prior to an event, scatter various RFID/Biosensors on or around intended routes or areas. During event, interrogate RFID/Biosensors. Sub-second explosive detection capability.

Proposed RFID/Biosensor (2) Robust enough to be deployed via aircraft, vehicles or individuals. Sample the surrounding environment. Biolayer longevity of 1 – 2 weeks Can be interrogated at anytime with built in anti-collision capability. Able to return modified interrogation signal in microseconds.

Proposed RFID/Biosensor (3) Stable, each biosensor has a built in reference. Low cost, no silicon electronics on chip, single metal layer plus microlitres of biosolution. Able to achieve reasonable shelf life. Able to operate in various climates Disables itself after termination of the biolayer.

Conclusions Have detected various explosive substances with acoustic wave biosensors. Have developed specific antibody techniques for 2D and 3D mapping algorithms of explosives and interferes. Have begun experiments on a 2.45 GHz RFID/Biosensor.