title: Electrochemical detection of fluoroquinolone antibiotics in milk using a magneto immunosensor.
abstract: An amperometric magneto-immunosensor (AMIS) for the detection of residues of fluoroquinolone antibiotics in milk samples is described for the first time. The immunosensor presented combines magnetic beads biomodified with an antibody with a broad recognition profile of fluoroquinolones, a haptenized enzyme and a magnetic graphite-epoxy composite (m-GEC) electrode. After the immunochemical reaction with specific enzyme tracer, the antibody biomodified magnetic beads are easily captured by an electrode made of graphite-epoxy composite containing a magnet, which also acts as transducer for the electrochemical detection. In spite of the complexity of milk, the use of magnetic beads allows elimination of potential interferences caused by the matrix components; hence the AMIS could perform quantitative measurements, directly in these samples, without any additional sample cleanup or extraction step. The immunosensor is able to detect up to seven different fluoroquinolones far below the MRLs defined by the UE for milk; for example ciprofloxacin is detected directly in milk with an IC50 of 0.74 µg/L and a LOD of 0.009 µg/L. This strategy offers great promise for rapid, simple, cost-effective, and on-site analysis fluoroquinolones in complex samples.
authors.affiliation: Nanobiotechnology for Diagnostics Group (Nb4D), IQAC-CSIC and CIBER de Bioingeniería, Biotemateriales y Nanomedicina, c/ Jordi Girona 18-26, 08034 Barcelona, Spain. daniel.gonzalez@iqac.csic.es.
authors.forename: Daniel G
authors.initials: DG
authors.lastname: Pinacho
authors.affiliation: Nanobiotechnology for Diagnostics Group (Nb4D), IQAC-CSIC and CIBER de Bioingeniería, Biotemateriales y Nanomedicina, c/ Jordi Girona 18-26, 08034 Barcelona, Spain.
authors.forename: Francisco
authors.initials: F
authors.lastname: Sánchez-Baeza
authors.affiliation: Sensors & Biosensors Group, Autonomous University of Barcelona (UAB), 08013 Bellaterra, Barcelona, Spain. Isabel.Pividori@uab.cat.
authors.forename: María-Isabel
authors.initials: MI
authors.lastname: Pividori
authors.affiliation: Nanobiotechnology for Diagnostics Group (Nb4D), IQAC-CSIC and CIBER de Bioingeniería, Biotemateriales y Nanomedicina, c/ Jordi Girona 18-26, 08034 Barcelona, Spain. pilar.marco@iqac.csic.es.
authors.forename: María-Pilar
authors.initials: MP
authors.lastname: Marco
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000032:analysis; D015374:Biosensing Techniques / Q000295:instrumentation; D003217:Conductometry / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D024841:Fluoroquinolones / Q000032:analysis*; D005504:Food Analysis / Q000295:instrumentation*; D005506:Food Contamination / Q000032:analysis*; D007118:Immunoassay / Q000295:instrumentation*; D018189:Immunomagnetic Separation / Q000295:instrumentation*; D008892:Milk / Q000737:chemistry*
chemical_list: D000900:Anti-Bacterial Agents; D024841:Fluoroquinolones