서강대학교

초록/요약

This paper proposed a quantum dot (Qdot)-aptamer beacon-based biosensor for user-friendly and highly sensitive detection of airborne influenza A (H1N1) virus using emission light guidance in 3-dimensional (3D) photonic crystal (PC). For easy to use, we present a fluorescent probe-based ‘Off-On’ detection protocol: first, a mixture composed of Qdot-aptamer beacons and dark quencher-labeled guard DNA (G-DNA) was prepared, and hence, it has initially quenched fluorescent signals with significantly low intensity, i.e. ‘Off’ state. In the presence of the influenza A (H1N1) virus, the influenza A (H1N1) virus binds to aptamer preferably and the G-DNA is released, so that the fluorescent signal is restored and the biosensor turns to ‘On’ state. The recovery efficiency of the fluorescence signal changes quantitatively according to the concentration of the target influenza A (H1N1) virus. Owing to emission light guidance of the 3D nanoporous PC structure, we achieved not only high sensitivity with an ultra-low limit of detection (LOD) of 138 pg/ml but also high selectivity over other species of influenza A virus or biomolecules. Additionally, with the benefit of the enhanced output fluorescent signals, the target virus can be easily detected with only a low-cost and portable home-made setup (total cost of only 20 US dollars) and a built-in camera in smartphone.