Mycobacterium tuberculosis strain H37Rv Electrochemical Sensor Mediated by Aptamer and AuNPs–DNA

Abstract

The accurate and rapid detection of Mycobacterium tuberculosis (M. tuberculosis) is essential for the effective treatment of tuberculosis. In this article, we propose an electrochemical sensor to detect M. tuberculosis reference strain H37Rv. The sensor contains an H37Rv aptamer and oligonucleotides modified with gold nanoparticles (AuNPs− DNA). An H37Rv aptamer screened by our laboratory was used as the recognition probe. The change in frequency shift mediated by AuNPs−DNA in the presence of H37Rv was detected using a multichannel series piezoelectric quartz crystal (MSPQC) system. Three oligonucleotides modified with gold nanoparticles were designed. These oligonucleotides contained 12, 12, and 13 bases that hybridized with the 37-nt H37Rv aptamer. H37Rv aptamer was immobilized on the gold electrode surface by Au−S bonds. A conductive-layer was then formed by sequential hybridization of the aptamer with the three designed AuNPs−DNAs. When H37Rv was present, it specifically bound to the aptamer, resulting in the detachment of AuNPs−DNA from the electrode. The conductive layer was thereby replaced by a nonconductive complex of aptamer and bacteria. These changes were monitored by the MSPQC system. The proposed sensor is rapid, specific and sensitive, the detection time was 2 h. The detection limit was 100 cfu/mL. This sensor would be of great benefit for the early clinical diagnosis of tuberculosis.

Polychlorinated Biphenyl Electrochemical Aptasensor Based on a Diamond–Gold Nanocomposite to Realize a Sub-Femtomolar Detection Limit

“… 19 , 20 Au-nanoparticles (Au-NPs) with large specific surface area would provide more adsorption sites for aptamers by forming Au–S bonds. 21 − 24 Carbon nanomaterials are key components of transducers in biosensors due to their intrinsic chemical and mechanical properties. 25 Boron-doped diamond (BDD) is an excellent carbon material for electrochemical examinations 26 because of its chemical inertness, wide potential window, low background current, and good electrochemical stability.…”

Advances in airborne microorganisms detection using biosensors: A critical review

“…Seo et al constructed a FET biosensor, detected the spike protein of SARS-CoV-2 at a concentration of 1 fg/mL, and successfully detected the culture medium (detection limit 16 PFU/ mL) and clinical specimens (detection limit 2.42 Â 10 2 copies/mL) of SARS-CoV-2 (Seo et al, 2020). Zhang developed a new type of piezoelectric sensor combined with aptamer technology to detect MTB with a limit of 100 CFU/mL (Zhang et al, 2019b).…”

“…Zhang developed a biosensor based on Exonuclease III (Exo III)-assisted target recovery, which can recognize hybrid double strands and selectively digest DNA capture probes. This process improved the sensor's sensitivity, and it can detect 20 CFU/mL MTB (Zhang et al 2019b). Liu et al improved the silicon photonic microcircle sensor using recombinase polymerase amplification technology, which increased the detection sensitivity of the sensor by three times (Liu et al, 2018c).…”

Design Strategies for Electrochemical Aptasensors for Cancer Diagnostic Devices

“…Such nanomaterials as silica and noble metal (Au, Ag, Pt, Pd) nanoparticles (NPs), graphene oxide (GO), and carbon nanotubes and their nanocomposites and nanohybrids, polymers and metal (Zn, Zr, Ce, Hf, Gd, Sn, Mn, Fe) oxides are actively used in the electrochemical aptasensor construction [80][81][82][83][84][85][86][87][88][89]. Electrochemical nanomaterial-based aptasensors are numerously reported in biomedical research [90][91][92][93] and may satisfy a huge demand for portable analytical devices with the selectivity and specificity sufficient for healthcare applications, such as POCT of biomarkers for chronic and emerging diseases: cancer, neurodegenerative disorders, cardiovascular diseases and chronic respiratory infections [94]. The unique properties of the aptamers stimulate the further development of innovative principles of such electrochemical aptasensor operation [95,96], and currently the electrochemical aptasensor-related articles represent ca.…”