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.

Chemical and biochemical analysis on lab-on-a-chip devices fabricated using three-dimensional printing

“…Since its invention in the late 1980s, 3D printing offers the opportunity for manufacturers to circumvent the time-consuming steps of traditional manufacturing technology via a full-scale or scaled-down mechanical replica of the products designed by computers [46][47][48][49]. A broad range of research components, including chemical reaction-ware [40,44,48,50], gradient generators [51,52], instrumental setups and interfaces [53][54][55][56][57], droplet extractors [52], and user-oriented functional devices [58][59][60][61] have been successfully built with the aid of 3D printing technologies confirming the feasibility of this approach. Further modification of 3D printed devices via adding chemicals or precursors of interest or post-printing surface functionalization extend the applicability of constructed products [45,62,63].…”

Recent advances in biological detection with magnetic nanoparticles as a useful tool

“…Lee et al [90] developed a novel 3D immunomagnetic flow assay for the rapid detection of pathogenic bacteria in a large-volume food sample ( Figure 4(a)). Antibody-modified magnetic nanoparticle clusters (AbMNCs) were immobilized on the surface of a 3D-printed cylindrical microchannel by an external applied magnetic field.…”

“…(a) Schematic illustrations of 3D immunomagnetic flow assay[90]; (b) schematic illustration of the multiplexed electrochemical immunoassay protocol and the measurement principles of the sandwich immunoassay[95]; (c) schematic of LAM with thrombin as the analyte and dose-response curve for the detection of thrombin by LAM[96].…”

3D-Printed Microfluidic Platform Enabling Bacterial Preconcentration and DNA Purification for Molecular Detection of Pathogens in Blood

“…Most recently, we have demonstrated that a 3D-printed µFD (3DpμFD) is an excellent platform for detecting pathogens because of its high speed, integration, and automation [17] Compared to photolithography and soft lithography, 3D printing has many advantages when printing μFDs because this technique easily enables printing high aspect ratio structures and does not require complex binding steps to form a monolithic structure. In recent years, considerable efforts have been devoted to the development of 3D printing microfluidic platforms for separation and detection [17][18][19]. However, to the best of our knowledge, there have been no reports showing that both IMS and DNA purification functions were integrated into a single device.…”