An ultrasensitive electrochemical biosensor for microRNA-21 detection via AuNPs/GAs and Y-shaped DNA dual-signal amplification strategy

Abstract

Herein, a gold nanoparticles/graphene aerogel (AuNPs/GAs) modified electrochemical biosensor compounded with catalytic hairpin assembly (CHA) and Y-shaped DNA nanostructure dual signal amplification approaches for the ultrasensitive microRNA-21 (miR-21) detection was...

Fe Single-Atom Carbon Dots Nanozyme Collaborated with Nucleic Acid Exonuclease III-Driven DNA Walker Cascade Amplification Strategy for Circulating Tumor DNA Detection

“…Furthermore, the straightforward analysis of ctDNA would be difficult and could be reasonably converted to other biological signals . In terms of flexibility, affordability, simplicity of operation, and potential applications in even detection, electrochemical biosensors have received much attention in recent years. , Presently, the buildup of electrochemical biosensing platforms in which nanomaterials and isothermal amplification strategies are used has great advantages in improving the sensitivity and accuracy of detectors. , Nanozymes are classified as quantum nanomaterials that catalog the enzymatic substrate chemical reaction by following enzyme kinetics under physiological conditions . In a few years, single-atom nanozymes have been emerging as a flashpoint for research due to their abundant and atomically dispersed individual active metal atoms, which can show excellent natural enzyme activity.…”

“…Reduced graphene oxide (rGO) is a honeycomb-arranged two-dimensional membrane construction derived through the graphene oxide (GO) as a substrate material . It has better electrical conductivity, favoring the responsiveness of the transducer. , In recent years, gold nanocrystals have received growing attention in medical and biosensing research owing to their exceptional physicochemical properties and biological affinity. − Among them, gold nanoparticles (AuNPs) are the commonest accessory elements in nanohybridized biosensors that not only immobilize a vast quantity of identifying elements, biomolecules, but also expedite the speed of electron transport at the face of the poles . Hence, the combination of rGO and AuNPs collectively strengthens the sensitivity and stability of the sensing electrodes.…”

Enzyme‐Free Fluorescent Detection of MicroRNA in Clinical Samples by Catalytic Hairpin Assembly Coupled with Magnetic Bead‐Confined 3D DNA Walking

“…[4a] In particular, CHA is convenient to transduce the invisible features of the analyte into readable digital signals, such as colorimetry, [13] fluorescent [14] and electrochemical signals. [15] A single CHA provides a general and efficient freeenergy-driven amplification principle with programing design, which yields hundreds-fold catalytic amplification of the target strand. [16] Indeed, in view of single CHA constrained by low signal gain, CHA is facilely conjugated with other amplification procedures to improve the sensitivity, [17] such as two-layered CHA reaction, the CHA-HCR system and the CHA-DNAzyme circuits.…”

“…Among the nonenzymatic technologies, the rapid, simple, highly sensitive and specific features of CHA strategy play important roles in miRNA sensing field [4a] . In particular, CHA is convenient to transduce the invisible features of the analyte into readable digital signals, such as colorimetry, [13] fluorescent [14] and electrochemical signals [15] . A single CHA provides a general and efficient free‐energy‐driven amplification principle with programing design, which yields hundreds‐fold catalytic amplification of the target strand [16] …”

A universal electrochemical biosensor based on CRISPR/Cas12a and a DNA tetrahedron for ultrasensitive nucleic acid detection

“…Electrochemical biosensors, known for their high sensitivity, rapid signal response, simplicity of operation, and ease of integration, have attracted considerable attention. 8 Recently, a universal electrochemical biosensor based on CRISPR/Cas, called E-CRISPR, has been widely established for nucleic acid detection. For instance, Zhang's team designed an electrochemical strategy mediated by CRISPR/Cas12a for interface cleavage of hairpin DNA reporter genes, achieving detection sensitivity as low as 30 pM of HPV-16.…”