title: Design of a toxicity biosensor based on Aliivibrio fischeri entrapped in a disposable card.
abstract: The degradation of the marine environment is a subject of concern for the European authorities primarily because of its contamination by hydrocarbons. The traditional methods (ISO 11348 standard) of general toxicity assessment are unsuitable in a context of in situ monitoring, such as seaports or bathing zones. Consequently, to address this issue, bacterial biosensors appear to be pertinent tools. This article presents the design of an innovative bioluminescent biosensor dedicated to in situ toxicity monitoring. This biosensor is based on the entrapment of the wild marine bioluminescent bacterial strain Aliivibrio fischeri ATCC® 49387™ in an agarose matrix within a disposable card. A pre-study was needed to select the most biological parameters. In particular, the regenerating medium's composition and the hydrogel concentration needed for the bacterial entrapment (mechanical resistance) were optimized. Based on these data, the ability of the bacterial reporter to assess the sample toxicity was demonstrated using naphthalene as a chemical model. The biosensor's results show a lower sensitivity to naphthalene (EC50 = 95 mg/L) compared with the results obtained using the reference method (EC50 = 43 mg/L). With this architecture, the biosensor is an interesting compromise among low maintenance, ease of use, appropriate sensitivity, relatively low cost and the ability to control online toxicity.
authors.affiliation: University of Nantes, UMR CNRS 6144 GEPEA-CBAC, 18 Boulevard Gaston Defferre, 85035, La Roche sur Yon, France.
authors.forename: Sulivan
authors.initials: S
authors.lastname: Jouanneau
authors.affiliation: University of Nantes, UMR CNRS 6144 GEPEA-CBAC, 18 Boulevard Gaston Defferre, 85035, La Roche sur Yon, France.
authors.forename: Marie-José
authors.initials: MJ
authors.lastname: Durand-Thouand
authors.affiliation: University of Nantes, UMR CNRS 6144 GEPEA-CBAC, 18 Boulevard Gaston Defferre, 85035, La Roche sur Yon, France. gerald.thouand@univ-nantes.fr.
authors.forename: Gérald
authors.initials: G
authors.lastname: Thouand
mesh_terms: D048908:Aliivibrio fischeri / Q000737:chemistry / Q000187:drug effects*; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D004209:Disposable Equipment; D004784:Environmental Monitoring / Q000295:instrumentation / Q000379:methods*; D004867:Equipment Design; D008163:Luminescent Measurements; D012680:Sensitivity and Specificity; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000633:toxicity*
chemical_list: D014874:Water Pollutants, Chemical
keywords: Aliivibrio fischeri; Bioluminescence; Biosensor; Immobilized bacteria; In situ monitoring; Toxicity