PSI's Advanced Sensor Methods and Technology

Mar 28, 2018

In this month's newsletter, we highlight three of our technologies: radiological threat detection network, photodynamic therapy for cancer detection, and unmanned aerial vehicles. While these may seem unrelated, they share a common theme; that advanced sensor methods and technology, when used effectively, provide information that enables a much better outcome for each application.

Advanced Radioactive Threat Detection System

Terrorist attacks involving the use of proliferated radiological and special nuclear materials pose a potential threat to U.S. citizens and service members. Early detection of such materials and devices made from them is a critical part of the U.S. strategy to prevent attacks. Lower-cost and more sensitive detectors, along with innovative deployment strategies, could significantly enhance detection and deterrence of an attack (

Courtesy of DARPA
illustration courtesy of DARPA

As part of DARPA's SIGMA research team, Physical Sciences Inc. (PSI) is helping to revolutionize detection and deterrent capabilities for countering nuclear terrorism. PSI's advanced spectroscopic algorithms for clutter suppression and isotope identification, as well as our gamma detector technology, are an integral part of the SIGMA architecture. A key component of SIGMA involves developing novel approaches to achieve low-cost, high-efficiency, packaged radiation detectors with spectroscopic gamma and neutron sensing capability. The program seeks to leverage existing infrastructure to help enable these next-generation detectors and their deployment in order to demonstrate game-changing detection and deterrent systems. DARPA's SIGMA system has developed two types of radiation detectors: a large size and an inexpensive smartphone-sized mobile device that can be worn on a belt by police officers or others. The devices run on advanced software that can detect weak traces of radioactive materials. Those devices, networked with detectors along major roadways, bridges, and other fixed infrastructure, promise significantly enhanced awareness of radiation sources and greater advance warning of possible threats. The SIGMA detectors themselves do not emit radiation but detect gamma and neutron radiation emanating from sources.

For the full story: Radioactive Threat Detection System Completes Emergency Vehicle Test Deployment in Nation's Capital (
Other recent SIGMA-related news articles can be found at the following link:

For more information, contact:
Dr. Bogdan Cosofret, Vice President, Aerospace Systems
Telephone: (978) 689-0003

Optical Dosimeter-guided Photodynamic Therapy

Physical Sciences Inc. (PSI) has been awarded a contract from the National Institutes of Health to produce an integrated, imaging Photodynamic Therapy (PDT) dosimeter that will enable real-time feedback to control PDT light dose during cancer treatment applications and outcomes.

PDT Dosimeter
PSI's integrated imaging Photodynamic Therapy (PDT) dosimeter

PDT is a promising modality for cancer treatment. Typically, a laser is used to photo-excite a photosensitizer (PS) that subsequently collides with oxygen molecules promoting them to the metastable singlet delta state. Singlet oxygen molecules are believed to be the species that destroys cancerous cells during PDT. Despite the benefit of targeted PDT that kills tumors selectively with minimum effect on surrounding healthy tissues, the efficacy of PDT is hindered by the lack of accurate dosimeters for the singlet oxygen produced during the therapy.

PSI is developing a 2D imaging sensor for PS fluorescence and singlet oxygen luminescence that will help resolve this problem. We have developed a strategy for singlet oxygen and photosensitizer dosimetry that can be used with conventional, continuous wave (cw) PDT excitation sources. PSI, in collaboration with Dartmouth College, will use the dosimeter to optimize the individual treatment response of PDT, which is necessary to improve the outcomes of PDT in a clinical environment.

This research has the potential to significantly improve clinical PDT applications and outcomes. Real-time feedback of the distributions of PS and singlet oxygen during treatment will be a valuable tool for PDT researchers and clinicians. Eventually, it could lead to much higher efficacy in PDT treatments in the clinic by enabling physicians to intelligently adapt individual light doses for PDT to match the different responses of individual patients.

For more information, contact:
Dr. Steven Davis, Chief Scientist
Telephone: (978) 689-000

InstantEye News

"InstantEye Robotics Opens New Product Development Facility" InstantEye Robotics announced that it has opened a new facility dedicated to the development and manufacturing of its family of tactical unmanned aerial systems. The 33,000 square-foot facility - with integrated design labs, manufacturing lines, and indoor and outdoor flight arenas - was specifically designed to accommodate the unique needs of the InstantEye Mk-2 GEN3, GEN4 and GEN5 product lines.

"United States Marine Corps Orders 800 InstantEye Systems" InstantEye Robotics announced that it has received an order from PMA-263, the Navy and Marine Corps Small Tactical Unmanned Aircraft Systems Program Office, for an additional 800 InstantEye Mk-2 GEN3-A0 sUAS systems. The systems delivered under this contract will support deployed Marine infantry squads, providing organic surveillance and reconnaissance capabilities.

For more information on InstantEye, please visit:

Physical Sciences Inc. | | (978) 689-0003 |

© 2018 Physical Sciences Inc.

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