title: Magnetic nanoparticle-based immunoassay for rapid detection of influenza infections by using an integrated microfluidic system.
abstract: Magnetic manganese ferrite (MnFe2O4) nanoparticles with approximately 100nm in diameter were used to improve the performance of an immunoassay for detecting influenza infections. The synthesized nanoparticles were tested for long-term storage to confirm the stability of their thermal decomposition process. Then, an integrated microfluidic system was developed to perform the diagnosis process automatically, including virus purification and detection. To apply these nanoparticles for influenza diagnosis, a micromixer was optimized to reduce the dead volume within the microfluidic chip. Furthermore, the mixing index of the micromixer could achieve as high as 97% in 2seconds. The optical signals showed that this nanoparticle-based immunoassay with dynamic mixing could successfully achieve a detection limit of influenza as low as 0.007 HAU. When compared with the 4.5-μm magnetic beads, the optical signals of the MnFe2O4 nanoparticles were twice as sensitive. Furthermore, five clinical specimens were tested to verify the usability of the developed system.
  
  
  BACKGROUND
  In this study, magnetic manganese ferrite nanoparticles were used to improve the performance of a novel immunoassay for the rapid and efficient detection of influenza infections.
authors: Department of Power Mechanical Engineering, National Tsing Hua University, Hsinchu, Taiwan.
authors: Lien-Yu
authors: LY
authors: Hung
authors: Department of Chemistry, National Cheng Kung University, Tainan, Taiwan.
authors: Jui-Cheng
authors: JC
authors: Chang
authors: Department of Microbiology and Immunology, National Cheng Kung University, Tainan, Taiwan.
authors: Yi-Che
authors: YC
authors: Tsai
authors: Department of Chemistry, National Cheng Kung University, Tainan, Taiwan.
authors: Chih-Chia
authors: CC
authors: Huang
authors: Department of Microbiology and Immunology, National Cheng Kung University, Tainan, Taiwan.
authors: Chih-Peng
authors: CP
authors: Chang
authors: Department of Chemistry, National Cheng Kung University, Tainan, Taiwan. Electronic address: csyeh@mail.ncku.edu.tw.
authors: Chen-Sheng
authors: CS
authors: Yeh
authors: Department of Power Mechanical Engineering, National Tsing Hua University, Hsinchu, Taiwan; Institute of Biomedical Engineering, National Tsing Hua University, Hsinchu, Taiwan; Institute of NanoEngineering and Microsystems, National Tsing Hua University, Hsinchu, Taiwan. Electronic address: gwobin@pme.nthu.edu.tw.
authors: Gwo-Bin
authors: GB
authors: Lee
mesh_terms: D000818:Animals; D004285:Dogs; D052203:Ferrosoferric Oxide / Q000737:chemistry*; D006801:Humans; D007118:Immunoassay / Q000379:methods; D007251:Influenza, Human / Q000175:diagnosis*; D061985:Madin Darby Canine Kidney Cells; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation / Q000379:methods*; D053758:Nanoparticles / Q000737:chemistry*; D009975:Orthomyxoviridae / Q000737:chemistry / Q000276:immunology*; D012680:Sensitivity and Specificity
chemical_list: D052203:Ferrosoferric Oxide
keywords: Influenza; Microfluidics; Nanoparticles; Surface modification