title: Reduction of palladium and production of nano-catalyst by Geobacter sulfurreducens.
abstract: The present study is the first report on the ability of Geobacter sulfurreducens PCA to reduce Pd(II) and produce Pd(0) nano-catalyst, using acetate as electron donor at neutral pH (7.0 ± 0.1) and 30 °C. The microbial production of Pd(0) nanoparticles (NPs) was greatly enhanced by the presence of the redox mediator, anthraquinone-2,6-disulfonate (AQDS) when compared with controls lacking AQDS and cell-free controls. A cell dry weight (CDW) concentration of 800 mg/L provided a larger surface area for Pd(0) NPs deposition than a CDW concentration of 400 mg/L. Sample analysis by transmission electron microscopy revealed the formation of extracellular Pd(0) NPs ranging from 5 to 15 nm and X-ray diffraction confirmed the Pd(0) nature of the nano-catalyst produced. The present findings open the possibility for a new alternative to synthesize Pd(0) nano-catalyst and the potential application for microbial metal recovery from metal-containing waste streams.
authors.affiliation: División de Ciencias Ambientales, Instituto Potosino de Investigación Científica y Tecnológica (IPICYT), Camino a la Presa San José 2055, Col. Lomas 4ª. Sección, C. P. 78216, San Luis Potosí, SLP, Mexico.
authors.forename: Aurora M
authors.initials: AM
authors.lastname: Pat-Espadas
authors.forename: Elías
authors.initials: E
authors.lastname: Razo-Flores
authors.forename: J Rene
authors.initials: JR
authors.lastname: Rangel-Mendez
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Cervantes
mesh_terms: D000085:Acetates / Q000378:metabolism; D000880:Anthraquinones / Q000378:metabolism; D045302:Geobacter / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000378:metabolism / Q000648:ultrastructure; D010084:Oxidation-Reduction; D010165:Palladium / Q000378:metabolism*; D013696:Temperature; D014961:X-Ray Diffraction
chemical_list: D000085:Acetates; D000880:Anthraquinones; C408124:anthraquinone-2,6-disulfonate; D010165:Palladium