title: A point-of-use microfluidic device with integrated photodetector array for immunoassay multiplexing: Detection of a panel of mycotoxins in multiple samples.
abstract: For a point-of-use analytical device to be successful in real-world applications, it needs to be rapid, simple to operate and, ideally, able to multiplex the detection of several analytes and samples. Mycotoxin detection in food and feedstock in particular has become increasingly relevant as these toxins, such as ochratoxin A (OTA), aflatoxin B1 (AFB1) and deoxynivalenol (DON), are subject to strict regulations and recommendations in the European Union. A novel, simple, negative pressure-driven device with manually operated magnetic valves was developed and the simultaneous immunodetection of these three mycotoxins was demonstrated via the laminar flow patterning of probes in an area of ≈0.12mm2and subsequent chemiluminescence generation via HRP-labeled antibodies. The three mycotoxins were detected in less than 20min at concentrations of 100ng/mL for OTA and DON and 3ng/mL for AFB1, spiked in a sample under analysis and simultaneously compared to a toxin-free reference and a standard contaminated with critical target concentrations. The on-chip optical detection was performed in a single acquisition step by integrating a microfabricated array of 25×25µm2hydrogenated amorphous silicon (a-Si:H) photosensors below the microfluidic chip. The device presented in this work is simple and effective for point-of-use multiplexing of immunoassays and was applied in this work to the screening of mycotoxins.
authors.affiliation: Instituto de Engenharia de Sistemas e Computadores - Microsistemas e Nanotecnologias (INESC MN) and IN - Institute of Nanoscience and Nanotechnology, Lisbon, Portugal; IBB - Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal.
authors.forename: R R G
authors.initials: RRG
authors.lastname: Soares
authors.affiliation: Instituto de Engenharia de Sistemas e Computadores - Microsistemas e Nanotecnologias (INESC MN) and IN - Institute of Nanoscience and Nanotechnology, Lisbon, Portugal; IBB - Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal.
authors.forename: D R
authors.initials: DR
authors.lastname: Santos
authors.affiliation: Instituto de Engenharia de Sistemas e Computadores - Microsistemas e Nanotecnologias (INESC MN) and IN - Institute of Nanoscience and Nanotechnology, Lisbon, Portugal.
authors.forename: V
authors.initials: V
authors.lastname: Chu
authors.affiliation: IBB - Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal; Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal.
authors.forename: A M
authors.initials: AM
authors.lastname: Azevedo
authors.affiliation: IBB - Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal; Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal.
authors.forename: M R
authors.initials: MR
authors.lastname: Aires-Barros
authors.affiliation: Instituto de Engenharia de Sistemas e Computadores - Microsistemas e Nanotecnologias (INESC MN) and IN - Institute of Nanoscience and Nanotechnology, Lisbon, Portugal; Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal. Electronic address: joao.conde@tecnico.ulisboa.pt.
authors.forename: J P
authors.initials: JP
authors.lastname: Conde
mesh_terms: D016604:Aflatoxin B1 / Q000032:analysis*; D015374:Biosensing Techniques / Q000295:instrumentation*; D004867:Equipment Design; D005506:Food Contamination / Q000032:analysis; D006735:Horseradish Peroxidase / Q000737:chemistry; D007118:Immunoassay / Q000295:instrumentation*; D018796:Immunoconjugates / Q000737:chemistry; D056656:Lab-On-A-Chip Devices; D057230:Limit of Detection; D008163:Luminescent Measurements / Q000295:instrumentation; D009793:Ochratoxins / Q000032:analysis*; D014255:Trichothecenes / Q000032:analysis*
chemical_list: D018796:Immunoconjugates; D009793:Ochratoxins; D014255:Trichothecenes; C025589:ochratoxin A; D016604:Aflatoxin B1; D006735:Horseradish Peroxidase; C007262:deoxynivalenol
keywords: Laminar; Magnets; Multiplexing; Mycotoxins; Patterning; Photoconductors