The Development of G‐Quadruplex‐Based Assays for the Detection of Small Molecules and Toxic Substances

Abstract

G-Quadruplexes can be induced to form guanine-rich DNA sequences by certain small molecules or metal ions. In concert with an appropriate signal transducer, such as a fluorescent dye or a phosphorescent metal complex, the ligand-recognition event can be transduced into a luminescent response. This focus review aims to highlight recent examples of aptamer-based and metal-mediated G-quadruplex assays for the detection of small molecules and toxic substances in the last three years. We discuss the mechanisms and features of the different assays and present an outlook and a perspective for the future of this field.

G-quadruplex based biosensor: A potential tool for SARS-CoV-2 detection

“…Furthermore, G-quadruplex structure has been shown to have an impact on the whole life cycle of virus, including replication, recombination and gene expression control. G-quadruplex can be therefore used for detecting and inhibiting a whole range of viruses, such as hepatitis A virus (HAV) ( Ma et al, 2017 ), Epstein-Barr virus (EBV) ( Platella et al, 2017 ), cauliflower mosaic virus (CaMV) ( Ruggiero and Richter, 2018 ), SARS-CoV ( Tan et al, 2009 ) and simian virus 40 (SV40) ( Lago et al, 2017 ). The versatility and plasticity of the G-quadruplex forming sequences allow them to be used in different types of detection tests.…”

“…The versatility and plasticity of the G-quadruplex forming sequences allow them to be used in different types of detection tests. Several sensing strategies have been developed and combined with various sensors, such as quartz crystal microbalance (QCM), surface plasmon resonance (SPR), fluorescence, colorimetry, electrophoresis, electrochemistry, electrochemiluminescence (ECL) and field effect transistor ( Ma et al, 2017 ; Platella et al, 2017 ; Ruggiero and Richter, 2018 ; Tan et al, 2009 ).…”

“…It is therefore crucial to develop novel, sensitive biosensors for rapid and specific SARS-CoV-2 detection. G-quadruplex has been shown to inhibit and detect a wide variety of viruses, including severe acute respiratory syndrome coronavirus (SARS-CoV) ( Tan et al, 2009 ), human immunodeficiency virus (HIV) ( Liang et al, 2011 ), and hepatitis A virus (HAV) ( Ma et al, 2017 ). The G-quadruplex based biosensor is therefore a promising potential tool for SARS-CoV-2 detection.…”

Recent Progress and Development of G-Quadruplex-Based Luminescent Assays for Ochratoxin A Detection

“…The ability of certain small molecules and toxic substances to bind to G4s has stimulated the development of G4-based detection platforms (Ma et al, 2017 ). Molecules that can be detected by G4-based assays include amino acids, sugar, adenosine, food toxins, and peptides (Lim et al, 2009 ).…”

FaptaSyme: A Strategy for Converting a Monomer/Oligomer‐Nonselective Aptameric Sensor into an Oligomer‐Selective One

“…A series of α-syn-binding aptamers were isolated recently by Tsukakoshi et al [15] One of the aptamers, namely T-SO504 (5’-CAG GGG TGG GCA AAG GGC GGT GGT G) has a G-rich sequence and presumably forms a G-quadruplex structure [16] when bound to its target. This was used for splitting the aptamer sequence into two fragments between the G-rich regions according to the strategy introduced by us earlier.…”