title: A multi-biosensor based on immobilized Photosystem II on screen-printed electrodes for the detection of herbicides in river water.
abstract: A multi-biosensor for detection of herbicides and pollutants was constructed using various photosynthetic preparations as biosensing elements. The photosynthetic thylakoid from Spinacia oleracea L., Senecio vulgaris and its mutant resistant to atrazine were immobilized with (BSA-GA) on the surface of screen-printed sensors composed of a graphite-working electrode and Ag/AgCl reference electrode deposited on a polymeric substrate. The biosensor was composed of four flow cells with independent illumination of 650 nm to activate electron transfer in Photosystem II. The principle of the detection was based on the fact that herbicides selectively block electron transport activity in a concentration-dependent manner and that the four PSII biomediators show differential recognition activity toward herbicides. Changes of the activity were registered amperometrically as rate of photoreduction of the artificial electron acceptor DQ. The setup resulted in a reusable herbicide multibiosensor with a good stability (half-life of 16.7 h for spinach thylakoids) and limit of detection of about 10(-8) M for herbicides recovered in spring in river.
authors.affiliation: Institute of Crystallography (Section of IC-Bari), National Research Council of Italy (CNR), via Salaria km 29.300-00016, Monterotondo Scalo, Rome, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Touloupakis
authors.forename: L
authors.initials: L
authors.lastname: Giannoudi
authors.forename: S A
authors.initials: SA
authors.lastname: Piletsky
authors.forename: L
authors.initials: L
authors.lastname: Guzzella
authors.forename: F
authors.initials: F
authors.lastname: Pozzoni
authors.forename: M T
authors.initials: MT
authors.lastname: Giardi
mesh_terms: D000327:Adsorption; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D020099:Coated Materials, Biocompatible / Q000737:chemistry; D045424:Complex Mixtures / Q000032:analysis / Q000737:chemistry; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D004566:Electrodes; D004784:Environmental Monitoring / Q000295:instrumentation / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D017022:Flow Injection Analysis / Q000295:instrumentation* / Q000379:methods; D006540:Herbicides / Q000032:analysis* / Q000737:chemistry; D045332:Photosystem II Protein Complex / Q000032:analysis / Q000737:chemistry*; D011485:Protein Binding; D045483:Rivers / Q000737:chemistry*; D018511:Systems Integration; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D020099:Coated Materials, Biocompatible; D045424:Complex Mixtures; D006540:Herbicides; D045332:Photosystem II Protein Complex; D014874:Water Pollutants, Chemical