title: Ultrarapid detection of pathogenic bacteria using a 3D immunomagnetic flow assay.
abstract: We developed a novel 3D immunomagnetic flow assay for the rapid detection of pathogenic bacteria in a large-volume food sample. Antibody-functionalized magnetic nanoparticle clusters (AbMNCs) were magnetically immobilized on the surfaces of a 3D-printed cylindrical microchannel. The injection of a Salmonella-spiked sample solution into the microchannel produced instant binding between the AbMNCs and the Salmonella bacteria due to their efficient collisions. Nearly perfect capture of the AbMNCs and AbMNCs-Salmonella complexes was achieved under a high flow rate by stacking permanent magnets with spacers inside the cylindrical separator to maximize the magnetic force. The concentration of the bacteria in solution was determined using ATP luminescence measurements. The detection limit was better than 10 cfu/mL, and the overall assay time, including the binding, rinsing, and detection steps for a 10 mL sample took less than 3 min. To our knowledge, the 3D immunomagnetic flow assay described here provides the fastest high-sensitivity, high-capacity method for the detection of pathogenic bacteria.
authors.affiliation: Department of Chemical Engineering and ‡School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology (POSTECH) , San 31, Hyoja-dong, Nam-gu, Pohang, Korea.
authors.forename: Wonjae
authors.initials: W
authors.lastname: Lee
authors.forename: Donghoon
authors.initials: D
authors.lastname: Kwon
authors.forename: Boram
authors.initials: B
authors.lastname: Chung
authors.forename: Gyoo Yeol
authors.initials: GY
authors.lastname: Jung
authors.forename: Anthony
authors.initials: A
authors.lastname: Au
authors.forename: Albert
authors.initials: A
authors.lastname: Folch
authors.forename: Sangmin
authors.initials: S
authors.lastname: Jeon
mesh_terms: D000907:Antibodies, Bacterial / Q000737:chemistry* / Q000276:immunology; D055910:Antibodies, Immobilized / Q000737:chemistry* / Q000276:immunology; D004867:Equipment Design; D005516:Food Microbiology / Q000191:economics / Q000295:instrumentation*; D006801:Humans; D018189:Immunomagnetic Separation / Q000191:economics / Q000295:instrumentation*; D057230:Limit of Detection; D008163:Luminescent Measurements; D012475:Salmonella / Q000276:immunology / Q000302:isolation & purification*; D012480:Salmonella Infections / Q000382:microbiology*; D013997:Time Factors
chemical_list: D000907:Antibodies, Bacterial; D055910:Antibodies, Immobilized