학술논문

A Proof-of-Concept Electrochemical Cytosensor Based on Chlamydomonas reinhardtii Functionalized Carbon Black Screen-Printed Electrodes: Detection of Escherichia coli in Wastewater as a Case Study.
Document Type
Academic Journal
Author
Antonacci A; Institute of Crystallography, National Research Council, Department of Chemical Sciences and Materials Technologies, Via Salaria km 29.300, 00015 Monterotondo, Italy.; Arduini F; Institute of Crystallography, National Research Council, Department of Chemical Sciences and Materials Technologies, Via Salaria km 29.300, 00015 Monterotondo, Italy.; Department of Chemical Science and Technologies, University of Rome 'Tor Vergata', Via della Ricerca Scientifica, 00133 Rome, Italy.; SENSE4MED, via Renato Rascel 30, 00128 Rome, Italy.; Attaallah R; Faculty of Sciences and Techniques, Hassan II University of Casablanca, Casablanca 20000, Morocco.; Amine A; Faculty of Sciences and Techniques, Hassan II University of Casablanca, Casablanca 20000, Morocco.; Giardi MT; Institute of Crystallography, National Research Council, Department of Chemical Sciences and Materials Technologies, Via Salaria km 29.300, 00015 Monterotondo, Italy.; Biosensors S.r.l., Via degli Olmetti 44, Formello, 00060 Rome, Italy.; Scognamiglio V; Institute of Crystallography, National Research Council, Department of Chemical Sciences and Materials Technologies, Via Salaria km 29.300, 00015 Monterotondo, Italy.
Source
Publisher: MDPI Pub Country of Publication: Switzerland NLM ID: 101609191 Publication Model: Electronic Cited Medium: Internet ISSN: 2079-6374 (Electronic) Linking ISSN: 20796374 NLM ISO Abbreviation: Biosensors (Basel) Subsets: MEDLINE
Subject
Language
English
Abstract
Herein, we report a proof-of-concept algal cytosensor for the electrochemical quantification of bacteria in wastewater, exploiting the green photosynthetic alga Chlamydomonas reinhardtii immobilized on carbon black (CB) nanomodified screen-printed electrodes. The CB nanoparticles are used as nanomodifiers, as they are able to sense the oxygen produced by the algae and thus the current increases when algae are exposed to increasing concentrations of bacteria. The sensor was tested on both standard solutions and real wastewater samples for the detection Escherichia coli in a linear range of response from 100 to 2000 CFU/100 mL, showing a limit of detection of 92 CFU/100 mL, in agreement with the maximum E. coli concentration established by the Italian law for wastewater (less than 5000 CFU/100 mL). This bacterium was exploited as a case study target of the algal cytosensor to demonstrate its ability as an early warning analytical system to signal heavy loads of pathogens in waters leaving the wastewater treatment plants. Indeed, the cytosensor is not selective towards E. coli but it is capable of sensing all the bacteria that induce the algae oxygen evolution by exploiting the effect of their interaction. Other known toxicants, commonly present in wastewater, were also analyzed to test the cytosensor selectivity, with any significant effect, apart from atrazine, which is a specific target of the D1 protein of the Chlamydomonas photosystem II. However, the latter can also be detected by chlorophyll fluorescence simultaneously to the amperometric measurements. The matrix effect was evaluated, and the recovery values were calculated as 105 ± 8, 83 ± 7, and 88 ± 7% for 1000 CFU/100 mL of E. coli in Lignano, San Giorgio, and Pescara wastewater samples, respectively.