title: Electrochemical genosensing of Salmonella, Listeria and Escherichia coli on silica magnetic particles.
abstract: A magneto-genosensing approach for the detection of the three most common pathogenic bacteria in food safety, such as Salmonella, Listeria and Escherichia coli is presented. The methodology is based on the detection of the tagged amplified DNA obtained by single-tagging PCR with a set of specific primers for each pathogen, followed by electrochemical magneto-genosensing on silica magnetic particles. A set of primers were selected for the amplification of the invA (278 bp), prfA (217 bp) and eaeA (151 bp) being one of the primers for each set tagged with fluorescein, biotin and digoxigenin coding for Salmonella enterica, Listeria monocytogenes and E. coli, respectively. The single-tagged amplicons were then immobilized on silica MPs based on the nucleic acid-binding properties of silica particles in the presence of the chaotropic agent as guanidinium thiocyanate. The assessment of the silica MPs as a platform for electrochemical magneto-genosensing is described, including the main parameters to selectively attach longer dsDNA fragments instead of shorter ssDNA primers based on their negative charge density of the sugar-phosphate backbone. This approach resulted to be a promising detection tool with sensing features of rapidity and sensitivity very suitable to be implemented on DNA biosensors and microfluidic platforms.
authors.affiliation: Grup de Sensors i Biosensors, Departament de Química, Universitat Autònoma de Barcelona, 08193, Cerdanyola del Vallès (Bellaterra), Spain.
authors.forename: Susana
authors.initials: S
authors.lastname: Liébana
authors.affiliation: Grup de Sensors i Biosensors, Departament de Química, Universitat Autònoma de Barcelona, 08193, Cerdanyola del Vallès (Bellaterra), Spain.
authors.forename: Delfina
authors.initials: D
authors.lastname: Brandão
authors.affiliation: Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona, 08193, Cerdanyola del Vallès (Bellaterra), Spain.
authors.forename: Pilar
authors.initials: P
authors.lastname: Cortés
authors.affiliation: Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona, 08193, Cerdanyola del Vallès (Bellaterra), Spain.
authors.forename: Susana
authors.initials: S
authors.lastname: Campoy
authors.affiliation: Grup de Sensors i Biosensors, Departament de Química, Universitat Autònoma de Barcelona, 08193, Cerdanyola del Vallès (Bellaterra), Spain.
authors.forename: Salvador
authors.initials: S
authors.lastname: Alegret
authors.affiliation: Grup de Sensors i Biosensors, Departament de Química, Universitat Autònoma de Barcelona, 08193, Cerdanyola del Vallès (Bellaterra), Spain. Electronic address: Isabel.Pividori@uab.cat.
authors.forename: María Isabel
authors.initials: MI
authors.lastname: Pividori
mesh_terms: D004926:Escherichia coli / Q000235:genetics / Q000302:isolation & purification*; D008087:Listeria / Q000235:genetics / Q000302:isolation & purification*; D008280:Magnetics; D008855:Microscopy, Electron, Scanning; D016133:Polymerase Chain Reaction; D012475:Salmonella / Q000235:genetics / Q000302:isolation & purification*; D012822:Silicon Dioxide / Q000737:chemistry*
chemical_list: D012822:Silicon Dioxide
keywords: Electrochemical genosensor; Foodborne pathogens; Magneto electrode; Silica magnetic particles; Single-tagged amplicon