Electrochemical and AFM Characterization of G-Quadruplex Electrochemical Biosensors and Applications

Abstract

Guanine-rich DNA sequences are able to form G-quadruplexes, being involved in important biological processes and representing smart self-assembling nanomaterials that are increasingly used in DNA nanotechnology and biosensor technology. G-quadruplex electrochemical biosensors have received particular attention, since the electrochemical response is particularly sensitive to the DNA structural changes from single-stranded, double-stranded, or hairpin into a G-quadruplex configuration. Furthermore, the development of an increased number of G-quadruplex aptamers that combine the G-quadruplex stiffness and self-assembling versatility with the aptamer high specificity of binding to a variety of molecular targets allowed the construction of biosensors with increased selectivity and sensitivity. This review discusses the recent advances on the electrochemical characterization, design, and applications of G-quadruplex electrochemical biosensors in the evaluation of metal ions, G-quadruplex ligands, and other small organic molecules, proteins, and cells. The electrochemical and atomic force microscopy characterization of G-quadruplexes is presented. The incubation time and cations concentration dependence in controlling the G-quadruplex folding, stability, and nanostructures formation at carbon electrodes are discussed. Different G-quadruplex electrochemical biosensors design strategies, based on the DNA folding into a G-quadruplex, the use of G-quadruplex aptamers, or the use of hemin/G-quadruplex DNAzymes, are revisited.

Research progress of single molecule force spectroscopy technology based on atomic force microscopy in polymer materials: Structure, design strategy and probe modification

“…To a large extent, the structure of G‐quadruplex nucleic acid has high thermodynamic stability under close physiological conditions. [ 126–129 ] Biffi et al. reported that G‐quadruplex nucleic acid can be engineered to produce and apply structure‐specific antibodies, which can quantitatively deliver the structure of DNA G‐quadruplex in human cells.…”

The Red Color of Life Transformed – Synthetic Advances and Emerging Applications of Protoporphyrin IX in Chemical Biology

“…[18a], Notably, hemin binding for generation of DNAzymes with peroxidase‐like activity and for the development of molecular sensing devices has found widespread attention and has been discussed in several reviews , ,. [86a], Herein, we will focus on the use of PPIX and its Zn(II) complex in conjunction with G‐quadruplex structures as biosensors.…”

Rapid and selective electrochemical detection of pb2+ ions using aptamer-conjugated alloy nanoparticles

“…The electrostatic attractive force between the bimetallic NPs and GCE aided the uniform deposition of NPs. More details of the Pb 2+ -aptamer interaction can be found elsewhere [40][41][42][43][44][45].…”