A sensitive colorimetric DNA biosensor for specific detection of the HBV gene based on silver‐coated glass slide and G‐quadruplex‐hemin DNAzyme

Abstract

A sensitive colorimetric DNA biosensor for specific detection of single stranded oligonucleotide (ssDNA) is proposed in this paper. The biosensor is based on silver-coated glass (SCGS) and G-quadruplex-hemin DNAzyme. Capture DNA is immobilized on the surface of SCGS by Ag-S bond. Signal DNA can be used to hybridize with the target DNA which is selected from the Hepatitis B virus(HBV) gene as target HBV DNA, and the HRP-mimicking G-quadruplex-hemin DNAzyme can be formed through the function of a guanine-rich fragment from signal DNA to catalyze the oxidation of 2,2-azinobis(3-ethylbenzothiozoline)-6-sulfonicacid (ABTS ) by H O . The reaction will be monitored along the side of absorbance changes at 418 nm and it can be viewed by naked eye with the change of color as well. Upon addition of target Hepatitis B virus(HBV) DNA, signal DNA could bind on the surface of SCGS, and the concentration of G-quadruplex-hemin DNAzyme immobilizing on the surface of SCGS is depended on that of target HBV DNA. Under the optimum conditions, the absorption was proportional to the concentration of target HBV DNA over the range from 0.5 to 100 nM, with a detection limit of 0.2 nM. In addition, the biosensor is target specific and practicability. This assay might open a new avenue for applying in the diagnosis of HBV disease in the future.

Selection and applications of functional nucleic acids for infectious disease detection and prevention

“…Visual detection G-quadruplex-hemin DNAzyme has a similar function to HRP, which catalyzes the oxidation of colorless 2,2-azinobis(3-ethylbenzothiozoline)-6-sulfonicacid (ABTS2 − ) to the green ABTS radical by H 2 O 2 . This principle has been applied for the detection of HBV gene [126], DNA related to HIV [127], and dengue virus (DENV) [128]. Yin et al [129] constructed a visual biosensor with polystyrene (PS) electrospun nanofibrous membrane as a basement to enhance the DNAzyme catalysis efficiency.…”

Unified-amplifier based primer exchange reaction (UniAmPER) enabled detection of SARS-CoV-2 from clinical samples

“…In this respect, GQs are classified as DNA catalysts, that are also named as HRP mimicking DNAzymes or HRPzymes 35 , 36 . HRP mimicking DNAzymes produce either colorimetric 35 , 37 , 38 , 39 or chemiluminescence [40] signals depending on the substrate. 2,2’-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 3,3′- diaminobenzidine (DAB) and TMB produce colorimetric signals while luminol provides a chemiluminesence readout.…”

Label-free fluorescent aptasensor for chloramphenicol based on hybridization chain reaction amplification and G-quadruplex/N-methyl mesoporphyrin IX complexation

“…To improve the sensitivity of biosensors, various methods based on signal amplication strategies have been rapidly developed, including hybridization chain reaction (HCR) amplication, 30,31 polymerase chain reaction amplication, 32,33 rolling circle amplication, 34,35 and strand displacement amplication. 36,37 Among these strategies, HCR is considered to have great potential for signal amplication owing to its enzyme-free nature, simplicity, economy, isothermality, and excellent sensitivity. The HCR method has been extensively used in the determination of oligonucleotides, 38 proteins, 39 and tumor cells.…”