Rapid identification of bacteria is critical in clinical and food safety applications. This paper describes a novel instrument and data analysis method for identifying bacteria based on the measurement of laser light scattering as the beam interacts with bacterial cells suspended in water. A description of the technology is followed by an identification performance study for a set of strains from the genus Staphylococcus (the inclusive target organisms) and a set of non-Staphylococcus strains (the exclusive organisms). Staphylococcus and non-Staphylococcus cells were grown on sheep blood agar (SBA), tryptic soy agar, brain heart infusion (BHI) agar, or Luria-Bertani (LB) agar and identified based on how cells scattered light. Bacteria from the genus Staphylococcus grown on solid media were correctly identified more than 92% of the time. To determine whether the system could also identify bacteria grown in liquid culture, six different Staphylococcus strains and six different non-Staphylococcus strains were grown in tryptic soy broth, BHI broth, or LB broth. This system accurately identified all targeted Staphylococcus samples tested, and no misidentifications occurred. A single-blind identification experiment was also performed on human clinical isolates obtained from the Upper Peninsula Health System. Ninety blind-coded clinical bacterial isolates on SBA were tested to determine whether they were from the genus Staphylococcus. All Staphylococcus were accurately identified, and no misidentifications occurred. This study demonstrated the proof of concept of a novel system that can rapidly and accurately identify bacteria from pure culture based on cellular light-scattering properties.

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The Micro Imaging Technology (MIT) 1000 Rapid Microbial Identification (RMID) System is a device that uses the principles of light scattering coupled with proprietary algorithms to identify bacteria after being cultured and placed in a vial of filtered water. This specific method is for pure culture identification of Listeria spp. A total of 81 microorganisms (55 isolates) were tested by the MIT 1000 System, of which 25 were Listeria spp. and 30 a variety of other bacterial species. In addition, a total of 406 tests over seven different ruggedness parameters were tested by the MIT 1000 System to determine its flexibility to the specifications stated in the MIT 1000 System User Guide in areas where they might be deviated by a user to shorten the test cycle. Overall, MIT concluded that the MIT 1000 System had an accuracy performance that should certify this Performance Test Method for the identification of Listeria spp. This report discusses the tests performed, results achieved, and conclusions, along with several reference documents to enable a higher understanding of the technology used by the MIT 1000 System.

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The use of lasers in range finders, target designators, and as battlefield weapons presents a problem for todays strategic and tactical electro-optical sensors. The sensitivity of these sensor systems makes them easy targets for jamming, spoofing, and damage by lasers. This directly impacts their survivability and the success of their mission. Hardening sensor systems against real and potential laser threats has been undertaken as a countermeasure. In order to harden sensor systems, their susceptibility must be assessed, hardening concepts incorporated, and finally, the hardening of the sensor must be verified. The McDonnell Douglas High Energy Laser Test Facility has been involved in testing vulnerability and survivability of sensor systems for the past thirteen years.The sensor vulnerability and survivability testing capabilities of the McDonnell Douglas High Energy Laser Test Facility are described. The lasers, instrumentation, and beam characterization capabilities as well as the threat simulation capabilities are discussed. Finally, test setups for several sensor systems tested in this facility are also discussed.