title: Lab-on-a-chip for multiplexed biosensing of residual antibiotics in milk.
abstract: A multiplexed immunoassay-based antibiotic sensing device integrated in a lab-on-a-chip format is described. The approach is multidisciplinary and involves the convergent development of a multi-antibiotic competitive immunoassay based on sensitive wavelength interrogated optical sensor (WIOS) technology and a polymer-based self-contained microfluidic cartridge. Immunoassay solutions are pressure-driven through external and concerted actuation of a single syringe pump and multiposition valve. Moreover, the use of a novel photosensitive material in a 'one step' fabrication process allowed the rapid fabrication of microfluidic components and interconnection port simultaneously. Pre-filled microfluidic cartridges were used as binary response rapid tests for the simultaneous detection of three antibiotic families - sulfonamides, fluoroquinolones and tetracyclines - in raw milk. For test interpretation, any signal lower than the threshold value obtained for the corresponding Maximum Residue Limit (MRL) concentration (100 microg L(-1)) was considered negative for a given antibiotic. The reliability of the multiplexed detection system was assessed by way of a validation test carried out on a series of six blind milk samples. A test accuracy of 95% was calculated from this experiment. The whole immunoassay procedure is fast (less than 10 minutes) and easy to handle (automated actuation).
authors.affiliation: CSEM Centre Suisse d'Electronique et Microtechnique SA, Jaquet-Droz 1, CH-2002 Neuchâtel, Switzerland. guillaume.suarez@csem.ch
authors.forename: Guillaume
authors.initials: G
authors.lastname: Suárez
authors.forename: Young-Hyun
authors.initials: YH
authors.lastname: Jin
authors.forename: Janko
authors.initials: J
authors.lastname: Auerswald
authors.forename: Stefan
authors.initials: S
authors.lastname: Berchtold
authors.forename: Helmut F
authors.initials: HF
authors.lastname: Knapp
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Diserens
authors.forename: Yves
authors.initials: Y
authors.lastname: Leterrier
authors.forename: Jan-Anders E
authors.initials: JA
authors.lastname: Månson
authors.forename: Guy
authors.initials: G
authors.lastname: Voirin
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000032:analysis*; D015374:Biosensing Techniques / Q000295:instrumentation*; D004350:Drug Residues / Q000032:analysis*; D024841:Fluoroquinolones / Q000032:analysis; D007118:Immunoassay; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D008892:Milk / Q000737:chemistry*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013449:Sulfonamides / Q000032:analysis; D013754:Tetracyclines / Q000032:analysis
chemical_list: D000900:Anti-Bacterial Agents; D024841:Fluoroquinolones; D013449:Sulfonamides; D013754:Tetracyclines