title: Colorimetric As (V) detection based on S-layer functionalized gold nanoparticles.
abstract: Herein, we present simple and rapid colorimetric and UV/VIS spectroscopic methods for detecting anionic arsenic (V) complexes in aqueous media. The methods exploit the aggregation of S-layer-functionalized spherical gold nanoparticles of sizes between 20 and 50 nm in the presence of arsenic species. The gold nanoparticles were functionalized with oligomers of the S-layer protein of Lysinibacillus sphaericus JG-A12. The aggregation of the nanoparticles results in a color change from burgundy-red for widely dispersed nanoparticles to blue for aggregated nanoparticles. A detailed signal analysis was achieved by measuring the shift of the particle plasmon resonance signal with UV/VIS spectroscopy. To further improve signal sensitivity, the influence of larger nanoparticles was tested. In the case of 50 nm gold nanoparticles, a concentration of the anionic arsenic (V) complex lower than 24 ppb was detectable.
authors.affiliation: Dresden University of Technology, Institute of Materials Science, Max Bergmann Center of Biomaterials, Budapester Strasse 27, 01069 Dresden, Germany. Electronic address: Mathias.Lakatos@tu-dresden.de.
authors.forename: Mathias
authors.initials: M
authors.lastname: Lakatos
authors.affiliation: Helmholtz-Zentrum Dresden-Rossendorf, Helmholtz Institute Freiberg for Resource Technology, Halsbruecker Strasse 34, 09599 Freiberg, Germany.
authors.forename: Sabine
authors.initials: S
authors.lastname: Matys
authors.affiliation: Helmholtz-Zentrum Dresden-Rossendorf, Helmholtz Institute Freiberg for Resource Technology, Halsbruecker Strasse 34, 09599 Freiberg, Germany; Helmholtz-Zentrum Dresden-Rossendorf, Institute of Resource Ecology, Bautzner Landstraße 400, 01328 Dresden, Germany.
authors.forename: Johannes
authors.initials: J
authors.lastname: Raff
authors.affiliation: Dresden University of Technology, Institute of Materials Science, Max Bergmann Center of Biomaterials, Budapester Strasse 27, 01069 Dresden, Germany.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Pompe
mesh_terms: D001151:Arsenic / Q000032:analysis* / Q000737:chemistry; D001406:Bacillaceae; D001426:Bacterial Proteins / Q000737:chemistry*; D003124:Colorimetry; D006046:Gold / Q000737:chemistry*; D008562:Membrane Glycoproteins / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*
chemical_list: D001426:Bacterial Proteins; D008562:Membrane Glycoproteins; C055764:S-layer proteins; D006046:Gold; D001151:Arsenic
keywords: Arsenic; Colorimetric; Detection; Nanoparticle; S-layer