title: A miniaturized bismuth-based sensor to evaluate the marine organism Styela plicata bioremediation capacity toward heavy metal polluted seawater.
abstract: Cadmium and lead are highly toxic heavy metals which cause a severe worldwide pollution. In addition to the toxic effect produced by the direct exposure, they can be bioconcentrated and accumulated in living organisms, including humans. Herein, a miniaturized and disposable electrochemical sensor was improved for the simultaneous detection of cadmium and lead ions to study the bioremediation of polluted seawater in presence of the filter-feeding marine organism Styela plicata. A screen-printed electrode modified in situ with a bismuth film was selected using the anodic stripping analysis as detection technique. This sensor was coupled with a portable potentiostat and the detection of cadmium and lead ions was carried out by Square Wave Anodic Stripping Voltammetry, allowing the simultaneous detection of both heavy metals at ppb level (LOD=0.3ppb for lead, 1.5ppb for cadmium). This analytical tool was then applied to assess the bioremediation capacity of S. plicata through a bioremediation experiment, in which the organism has been exposed to seawater artificially polluted with 1000ppb of Cd2+and Pb2+. The matrix effect of both seawater and acid digested biological samples was evaluated. A bioconcentration phenomenon was observed for both heavy metals through the analysis of S. plicata tissues. In details, Pb2+resulted to be about 2.5 times more bioconcentrated than Cd2+, giving an effective bioremediation level in seawater of 13% and 40% for Cd2+and Pb2+, respectively. Thus, our results demonstrate the capability of S. plicata to bioremediate Cd2+and Pb2+polluted seawater as well as the suitability of the electrochemical sensor for contaminated marine environment monitoring and bioremediation evaluation.
authors.affiliation: Department of Chemical Science and Technology, University of Rome "Tor Vergata", via della Ricerca Scientifica, 00133 Rome, Italy.
authors.forename: Noemi
authors.initials: N
authors.lastname: Colozza
authors.affiliation: Department of Biology, University of Rome "Tor Vergata", via della Ricerca Scientifica, 00133 Rome, Italy.
authors.forename: Maria Flavia
authors.initials: MF
authors.lastname: Gravina
authors.affiliation: ArpaLazio, Via Giuseppe Saredo 52, 00173 Rome, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Amendola
authors.affiliation: ArpaLazio, Via Giuseppe Saredo 52, 00173 Rome, Italy.
authors.forename: Modesto
authors.initials: M
authors.lastname: Rosati
authors.affiliation: Laboratory of Hydrometallurgy and Inorganic Molecular Chemistry, Faculty of Chemistry, USTHB, BP32, El-Alia, 16111 Bab Ezzouar, Algiers, Algeria.
authors.forename: Djamal Eddine
authors.initials: DE
authors.lastname: Akretche
authors.affiliation: Department of Chemical Science and Technology, University of Rome "Tor Vergata", via della Ricerca Scientifica, 00133 Rome, Italy.
authors.forename: Danila
authors.initials: D
authors.lastname: Moscone
authors.affiliation: Department of Chemical Science and Technology, University of Rome "Tor Vergata", via della Ricerca Scientifica, 00133 Rome, Italy. Electronic address: fabiana.arduini@uniroma2.it.
authors.forename: Fabiana
authors.initials: F
authors.lastname: Arduini
mesh_terms: D000818:Animals; D001673:Biodegradation, Environmental; D001729:Bismuth; D002104:Cadmium / Q000302:isolation & purification; D004566:Electrodes; D007854:Lead / Q000302:isolation & purification; D019216:Metals, Heavy / Q000302:isolation & purification*; D012623:Seawater / Q000737:chemistry*; D014561:Urochordata; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*
chemical_list: D019216:Metals, Heavy; D014874:Water Pollutants, Chemical; D002104:Cadmium; D007854:Lead; D001729:Bismuth
keywords: Ascidians; Bioremediation; Environmentally-friendly electrochemical sensor; In situ analysis; Lead and cadmium pollution