A reagent-ready-on-chip microfluidic immunoassay system for rapid detection of influenza A H1N1 and H3N2 viruses

Development of effective disease screening method is the best approach for the control of infectious diseases. However, conventional screening methods require to operate in well-equipped laboratory. That makes the screening operation expensive and time-consuming. In this work, a reagent-ready-on-chip microfluidic immunoassay system was developed and rapid detection of influenza A H1N1 and H3N2 viruses was demonstrated to show its simplicity and rapidity. The microfluidic system integrated 4 single-stroke ther-mopneumatic actuators and a reaction chamber. All related reagents were pre-installed in the system and manipulated automatically for indirect immunoassay. Detection of influenza A H1N1 and H3N2 viruses based on its internal structure protein, i.e., nucleoprotein (NP), was demonstrated using the system. Result was represented by colorimetric signal in the reaction chamber. The use of thermopneumatic actuation could achieve fluid manipulation without external assistive equipment and colorimetric result could be observed directly without the need of external dedicated detector. Influenza virus screening could be completed around 1 hour with less sample volume (20 μL) and reagent volume (50 μL). The system achieved one-step operation of immunoassay. It is highly integrated and has potential to be developed to portable devices to realize rapid diagnostics in remote environment and clinics without well-equipped facility.