title: Investigation of amperometric detection of phosphate Application in seawater and cyanobacterial biofilm samples.
abstract: Detection of phosphate using amperometry was investigated. The phosphomolybdate complex, formed by addition of nitric acid, ammonium molybdate and phosphate, was reduced at a carbon paste electrode polarised at +0.3V (versus Ag/AgCl). The major characteristics observed were simplicity of the equipment, a limited consumption of reagents and a low detection limit (0.3mumoll(-1)), with a linear range between 1 and 20mumoll(-1). The interference of silicate was completely eliminated using an appropriate concentration of nitric acid and ammonium molybdate. The amperometric detection of orthophosphate in seawater using the batch injection analysis (BIA) technique was reported. Moreover, a carbon paste microelectrode was constructed. Its use allows the analysis of small volume of samples with little dilution in supporting electrolyte. This method was applied to the determination of orthophosphate in cyanobacterial biofilms collected from Roman catacombs. There was a good statistical correlation between results obtained with the proposed method and the standard spectrophotometric method.
authors.affiliation: Dipartimento di Scienze e Tecnologie Chimiche, Università di Roma Tor Vergata, Via della Ricerca Scientifica, 1, Rome 00133, Italy; Instituto de Materiales y Reactivos, Universidad de la Habana, Habana, Cuba.
authors.forename: Josefina Calvo
authors.initials: JC
authors.lastname: Quintana
authors.forename: Laila
authors.initials: L
authors.lastname: Idrissi
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Palleschi
authors.forename: Patrizia
authors.initials: P
authors.lastname: Albertano
authors.forename: Aziz
authors.initials: A
authors.lastname: Amine
authors.forename: Mama
authors.initials: M
authors.lastname: El Rhazi
authors.forename: Danila
authors.initials: D
authors.lastname: Moscone