Anti-DNA:RNA Antibodies and Silicon Photonic Microring Resonator Arrays Enable the Ultrasensitive, Multiplexed Detection of microRNAs

• Published in: Analytical chemistry (Washington) Vol. 83; no. 15; pp. 5949 - 5956
• Main Authors: Qavi, Abraham J., Kindt, Jared T., Gleeson, Martin A., Bailey, Ryan C.
• Format: Journal Article
• Language: English
• Published: 29.06.2011
• ISSN: 0003-2700; 1520-6882
• DOI: 10.1021/ac201340s

In this paper, we present a method for the ultrasensitive detection of microRNAs (miRNAs) utilizing an antibody that specifically recognizes DNA:RNA heteroduplexes, using a silicon photonic microring resonator array transduction platform. Microring resonator arrays are covalently functionalized with DNA capture probes that are complementary to solution phase miRNA targets. Following hybridization on the sensor, the anti-DNA:RNA antibody is introduced and binds selectively to the heteroduplexes, giving a larger signal than the original miRNA hybridization due to the increased mass of the antibody, as compared to the 22 oligoribonucleotide. Furthermore, the secondary recognition step is performed in neat buffer solution and at relatively higher antibody concentrations, facilitating the detection of miRNAs of interest. The intrinsic sensitivity of the microring resonator platform coupled with the amplification provided by the anti-DNA:RNA antibodies allows for the detection of microRNAs at concentrations as low as 10 pM (350 attomoles). The simplicity and sequence generality of this amplification method position it as a promising tool for high-throughput, multiplexed miRNA analysis, as well as a range of other RNA based detection applications.