title: Photoluminescence detection of 2,4,6-trinitrotoluene (TNT) binding on diatom frustule biosilica functionalized with an anti-TNT monoclonal antibody fragment.
abstract: A selective and label-free biosensor for detection of the explosive compound 2,4,6-trinitrotoluene (TNT) in aqueous solution was developed based on the principle of photoluminescence quenching of upon immunocomplex formation with antibody-functionalized diatom frustule biosilica. The diatom frustule is an intricately nanostructured, highly porous biogenic silica material derived from the shells of microscopic algae called diatoms. This material emits strong visible blue photoluminescence (PL) upon UV excitation. PL-active frustule biosilica was isolated from cultured cells of the marine diatom Pinnularia sp. and functionalized with a single chain variable fragment (scFv) derived from an anti-TNT monoclonal antibody. When TNT was bound to the anti-TNT scFv-functionalized diatom frustule biosilica, the PL emission from the biosilica was partially quenched due to the electrophilic nature of the nitro (-NO2) groups on the TNT molecule. The dose-response curve for immunocomplex formation of TNT on the scFv-functionalized diatom frustule biosilica had a half-saturation binding constant of 6.4 ± 2.4·10(-8)M and statistically-significant measured detection limit of 3.5·10(-8)M. The binding and detection were selective for TNT and TNB (trinitrobenzene) but not RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) or 2,6-DNT (2,6-dinitrotoluene).
authors.affiliation: School of Chemical, Biological, and Environmental Engineering, Oregon State University, Corvallis, Oregon, 97331 USA.
authors.forename: Le
authors.initials: L
authors.lastname: Zhen
authors.affiliation: Marine Sciences Laboratory, Pacific Northwest National Laboratory, Sequim, WA, 98382 USA.
authors.forename: Nicole
authors.initials: N
authors.lastname: Ford
authors.affiliation: School of Chemical, Biological, and Environmental Engineering, Oregon State University, Corvallis, Oregon, 97331 USA.
authors.forename: Debra K
authors.initials: DK
authors.lastname: Gale
authors.affiliation: Marine Sciences Laboratory, Pacific Northwest National Laboratory, Sequim, WA, 98382 USA; Department of Microbiology, Oregon State University, Corvallis, Oregon, 97331 USA.
authors.forename: Guritno
authors.initials: G
authors.lastname: Roesijadi
authors.affiliation: School of Chemical, Biological, and Environmental Engineering, Oregon State University, Corvallis, Oregon, 97331 USA. Electronic address: rorrergl@engr.orst.edu.
authors.forename: Gregory L
authors.initials: GL
authors.lastname: Rorrer
mesh_terms: D055910:Antibodies, Immobilized / Q000737:chemistry; D000911:Antibodies, Monoclonal / Q000737:chemistry*; D015374:Biosensing Techniques / Q000379:methods; D017377:Diatoms / Q000737:chemistry* / Q000648:ultrastructure; D004136:Dinitrobenzenes / Q000032:analysis; D053834:Explosive Agents / Q000032:analysis*; D057230:Limit of Detection; D008163:Luminescent Measurements / Q000379:methods; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D012822:Silicon Dioxide / Q000737:chemistry; D057127:Single-Chain Antibodies / Q000737:chemistry; D014303:Trinitrotoluene / Q000032:analysis*; D014867:Water / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D055910:Antibodies, Immobilized; D000911:Antibodies, Monoclonal; D004136:Dinitrobenzenes; D053834:Explosive Agents; D057127:Single-Chain Antibodies; D014874:Water Pollutants, Chemical; D014867:Water; D014303:Trinitrotoluene; D012822:Silicon Dioxide; C023514:2,6-dinitrotoluene
keywords: Antibody; Biosensor; Biosilica; Diatom; Photoluminescence; Trinitrotoluene