An integrated self-driven microfluidic device for rapid detection of the influenza A (H1N1) virus by reverse transcription loop-mediated isothermal amplification

Influenza A is amongst the most infectious diseases of the past decade. Although rapid and accurate detection can efficiently prevent its spread, the sensitivity and specificity of current rapid influenza diagnostic tests (RIDTs) are relatively low. In this study, a self-driven microfluidic device was developed to rapidly detect the H1N1 influenza virus via a reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay. The device was capable of 1) virus isolation via H1N1-specific aptamers conjugated magnetic beads, 2) virus lysis, 3) isothermal nucleic acid amplification, and 4) colorimetric detection of the virus. The limit of detection was measured to be only 3 x 10(-4) hemagglutinating units (HAU)/reaction, which is sensitive enough for clinical applications. The entire procedure could be performed in only 40 min by capillary forces through a novel polydimethylsiloxane surface treatment in cooperation with hydrophobic soft valves. This is the first time that a simple, self-driven passive microfluidic chip has been demonstrated to be capable of performing sample pretreatment, RT-LAMP, and H1N1 virus detection on a single chip. This microfluidic chip may therefore serve a promising RIDT with high sensitivity and high specificity for point-of-care diagnostics in the near future.