Giampaolo Zuccheri
University of Bologna, Italy
Biography
Some of the possible perspective advantages of the uptake of nucleic acids biosensor technology are already within reach, still, sometimes, limited sensitivity can seriously inhibit the application of biosensor-based detection methods when these could be useful towards detection of nucleic acids variants present only at a very low concentration. While in a research lab, this objective is achieved using complex but sensitive amplification techniques, such as PCR, or the deployment of sophisticated sensitive detection techniques, this goal might prove a prohibitive objective for point-of-need biosensors. Recently, through knowledge and capabilities developed within the field of DNA nanotechnology, means to implement very specific molecular recognition and signal enhancement methods have been presented that could prove of direct application for biosensor detection methods. We have adapted and attempted at using the hybridization chain reaction (HCR) towards enhancing the signal due to the specific recognition and binding of soluble nucleic acids to a surface-bound probe. The enhancement strategy consists in a triggered supramolecular polymerization of DNA sequences or nanostructures at the location of specific nucleic acids recognition. We have showed that the method can be used towards the detection of an arbitrary DNA target through proper design of the sequences of the components. Preliminary experimental evidence shows a significant enhancement of the signal, which could prove useful in some applications. We also proved that HCR can have single-nucleotide sensitivity for the detection and signal enhancement. We recently extended the application of HCR towards the detection of miRNA targets. This strategy is compatible with several detection techniques that can be implemented on a lab-on-chip, such as electrochemistry or surface plasmon resonance, while it can also be measured via fluorescence and luminescence, achieving higher detection sensitivity.
Abstract
Abstract : Molecular self-assembly for signal enhancement in nucleic acids biosensors