Aptasensors for Detection of Avian Influenza Virus H5N1

Aptamers are single-stranded RNA or DNA oligonucleotides which have specific three-dimensional (3D) structures for high affinity and specific recognition to their target. In diagnostic and detection assays, aptamers represent an alternative to antibodies as recognition agents and offer advantages, such as reduced cost, rapid and reproducible synthesis, controllable modification, and improved stability. Aptamers are favorably used in biosensors as sensitive and selective bio-receptors coupled with a variety of transducers such as optical, mass-sensitive, and electrochemical sensors, the so-called aptasensors. We report the development of several types of aptasensors for rapid and specific detection of avian influenza virus (AIV) H5N1. DNA aptamers with high affinity and specificity against AIV H5N1 were immobilized on the electrode surface and then incorporated into different transducers such as surface plasmon resonance (SPR), quartz crystal microbalance (QCM) and electrochemical transducer. The target viruses were captured by the immobilized aptamers resulting in a detectable signal. The fabrication of aptasensors, detection principles, and their applications for AIV H5N1 detection are addressed.