title: Acidithiobacillus ferrooxidans fixation on mercuric surfaces and its application in stripping voltammetry.
abstract: The adsorption (fixation) of bacteria Acidithiobacillus ferrooxidans on Hg and Cu metallic surfaces was qualitatively studied owing to two independent methods: frequency measurement using a quartz crystal microbalance and light absorption measuring at the Hg/bacterial culture interface. A method using a dropping mercury electrode (DME) allowed quantifying this bacterial fixation. Determining the superficial tension at Hg/bacterial culture interface led to determine bacteria adsorption on Hg through the Gibbs isotherm. A modified stripping voltammetry was proposed taking benefit of both bacterial adsorption on Hg surface and metal fixation capacity on biomass. Metal preconcentration on the biologically modified Hg electrode appeared to improve the measurement sensitivity of differential pulse anodic stripping voltammetry (DPASV). The height of the detected peaks was thus increased of 17.6% for copper, 48.4% for lead, and 132% for cadmium determinations compared to those obtained with an unmodified mercury electrode. Such augmentation depended on bulk bacteria concentration and bacteria preconcentration.
authors.affiliation: Autonomous University of Baja California, Institute of Engineering, Blvd. Benito Juares S/N 21280, Mexicali, Baja California, Mexico.
authors.forename: Roumen
authors.initials: R
authors.lastname: Zlatev
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Magnin
authors.forename: Patrick
authors.initials: P
authors.lastname: Ozil
authors.forename: Margarita
authors.initials: M
authors.lastname: Stoytcheva
mesh_terms: D042763:Acidithiobacillus / Q000302:isolation & purification* / Q000502:physiology*; D001422:Bacterial Adhesion / Q000502:physiology; D001681:Biological Assay / Q000295:instrumentation / Q000379:methods*; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D015169:Colony Count, Microbial / Q000295:instrumentation / Q000379:methods*; D004563:Electrochemistry / Q000295:instrumentation / Q000379:methods*; D004566:Electrodes; D008628:Mercury / Q000737:chemistry*; D010783:Photometry / Q000379:methods
chemical_list: D008628:Mercury