title: Uranyl-specific binding at a functionalised interface: a chemophotonic fibre optic sensor platform.
abstract: Detection of radiological materials in the solution phase is restricted by conventional radiation-counting techniques owing to extreme attenuation. Chemical sensing of the resultant radiological species such as uranyl UO(2)(2+) is possible on the surface of a plastic or glass fibre optic. A dihydroxy isoamethryin complex is tethered to the fibre surface which has a large extinction coefficient (119 000 M(-1) cm(-1) at lambda = 439 nm) and changes colour upon binding UO(2)(2+). The spectral changes are greater on the surface than in solution and binding is specific to UO(2)(2+) with small interferences from Gd(3+). Monitoring the spectral response in three detector bands in the red, green and blue enable the optical power change to be measured with sensitivities of 1 mdB, allowing UO(2)(2+) to be detected confidently at 50-100 ppb levels. Real-time kinetic analysis enables discrimination between the target species and possible interferents.
authors.affiliation: EvanesCo Ltd, Forde Court, Forde Road, Newton Abbot, Devon, UK.
authors.forename: Neil W
authors.initials: NW
authors.lastname: Hayes
authors.forename: Clare J
authors.initials: CJ
authors.lastname: Tremlett
authors.forename: Patricia J
authors.initials: PJ
authors.lastname: Melfi
authors.forename: Jonathon D
authors.initials: JD
authors.lastname: Sessler
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Shaw
mesh_terms: D005336:Fiber Optic Technology; D009689:Nuclear Warfare; D019904:Polymethyl Methacrylate; D011868:Radioisotopes / Q000032:analysis*; D012637:Security Measures; D013053:Spectrophotometry / Q000295:instrumentation / Q000379:methods; D017974:Uranium Compounds; D014875:Water Pollutants, Radioactive / Q000032:analysis*
chemical_list: D011868:Radioisotopes; D017974:Uranium Compounds; D014875:Water Pollutants, Radioactive; D019904:Polymethyl Methacrylate