Rapid detection of influenza A virus infection utilizing an immunomagnetic bead-based microfluidic system

Abstract

This study reports a new immunomagnetic bead-based microfluidic system for the rapid detection of influenza A virus infection by performing a simple two-step diagnostic process that includes a magnetic bead-based fluorescent immunoassay (FIA) and an end-point optical analysis. With the incorporation of monoclonal antibody (mAb)-conjugated immunomagnetic beads, target influenza A viral particles such as A/H1N1 and A/H3N2 can be specifically recognized and are bound onto the surface of the immunomagnetic beads from the specimen sample. This is followed by labeling the fluorescent signal onto the virus-bound magnetic complexes by specific developing mAb with R-phycoerythrin (PE). Finally, the optical intensity of the magnetic complexes can be analyzed immediately by the optical detection module. Significantly, the limit of detection (LOD) of this immunomagnetic bead-based microfluidic system for the detection of influenza A virus in a specimen sample is approximately 5×10(-4) hemagglutin units (HAU), which is 1024 times better than compared to conventional bench-top systems using flow cytometry. More importantly, the entire diagnostic protocol, from the purification of target viral particles to optical detection of the magnetic complexes, can be automatically completed within 15 min in this immunomagnetic bead-based microfluidic system, which is only 8.5% of the time required when compared to a manual protocol. As a whole, this microfluidic system may provide a powerful platform for the rapid diagnosis of influenza A virus infection and may be extended for diagnosis of other types of infectious diseases with a high specificity and sensitivity.

Nanoparticle-based flow virometry for the analysis of individual virions

“…The exact tracing of virions to the cells that have produced them also requires the analysis of individual viral particles. Currently, the envelope composition of viruses is studied by analyzing viral preparations in bulk, although attempts to visualize viruses using flow cytometers have been made (5)(6)(7)(8)(9).…”

Optofluidics incorporating actively controlled micro- and nano-particles

“…Many optofluidic systems use the magnetic properties of particles for eventual bioapplications. An example of such manipulation is presented in the work of Lien et al 197 They used antibody conjugated magnetic beads (Ø4.5 lm) to detect and isolate influenza A viruses. Target influenza A virus, which was immobilized onto the surface of the magnetic beads.…”

Comparison of three magnetic-bead-based RNA extraction methods for detection of cucumber green mottle mosaic virus by real-time RT-PCR

“…Magnetic-bead-based methods for the separation and enrichment of targets include two types: specific and non-specific separations. Currently, the most widely used application is specific separation; this technology has been used in biomedical applications [8][9][10], food safety [11,12], environmental monitoring [13,14], and plant virus detection [15]. Previous studies have shown the development of magnetic-bead-based methods for the detection of CGMMV; this virus was successfully detected in cucumber seeds through specific virus adsorption with immunomagnetic beads (IMB) (coated with CGMMV antibody) followed by RT-PCR [16] and in cucumber leaves using an RT-PCR method combined with non-specific magnetic separation (MNP) (no CGMMV antibody coating) [17].…”