title: A biolayer interferometry-based assay for rapid and highly sensitive detection of biowarfare agents.
abstract: Biolayer interferometry (BLI) is an optical technique that uses fiber-optic biosensors for label-free real-time monitoring of protein-protein interactions. In this study, we coupled the advantages of the Octet Red BLI system (automation, fluidics-free, and on-line monitoring) with a signal enhancement step and developed a rapid and sensitive immunological-based method for detection of biowarfare agents. As a proof of concept, we chose to demonstrate the efficacy of this novel assay for the detection of agents representing two classes of biothreats, proteinaceous toxins, and bacterial pathogens: ricin, a lethal plant toxin, and the gram-negative bacterium Francisella tularensis, the causative agent of tularemia. The assay setup consisted of biotinylated antibodies immobilized to the biosensor coupled with alkaline phosphatase-labeled antibodies as the detection moiety to create nonsoluble substrate crystals that precipitate on the sensor surface, thereby inducing a significant wavelength interference. It was found that this BLI-based assay enables sensitive detection of these pathogens (detection limits of 10 pg/ml and 1 × 10(4) pfu/ml ricin and F. tularensis, respectively) within a very short time frame (17 min). Owing to its simplicity, this assay can be easily adapted to detect other analytes in general, and biowarfare agents in particular, in a rapid and sensitive manner.
authors.affiliation: Department of Infectious Diseases, Israel Institute for Biological Research, Ness-Ziona 74100, Israel.
authors.forename: Adva
authors.initials: A
authors.lastname: Mechaly
authors.affiliation: Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona 74100, Israel.
authors.forename: Hila
authors.initials: H
authors.lastname: Cohen
authors.affiliation: Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona 74100, Israel.
authors.forename: Ofer
authors.initials: O
authors.lastname: Cohen
authors.affiliation: Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona 74100, Israel. Electronic address: ohadm@iibr.gov.il.
authors.forename: Ohad
authors.initials: O
authors.lastname: Mazor
mesh_terms: D054045:Biological Warfare Agents; D015374:Biosensing Techniques / Q000379:methods*; D005604:Francisella tularensis / Q000302:isolation & purification*; D007368:Interferometry / Q000379:methods*; D008027:Light; D012276:Ricin / Q000032:analysis*; D013997:Time Factors; D014406:Tularemia / Q000382:microbiology*
chemical_list: D054045:Biological Warfare Agents; D012276:Ricin
keywords: Biolayer interferometry; Biowarfare agents; Octet; Ricin; Tularemia