Ultrasensitive biosensing platform based on layered vanadium disulfide–graphene composites coupling with tetrahedron-structured DNA probes and exonuclease III assisted signal amplification

2015 ◽  
Vol 3 (41) ◽  
pp. 8180-8187 ◽  
Author(s):  
Ke-Jing Huang ◽  
Yu-Jie Liu ◽  
Qiu-Fen Zhai
Keyword(s):  
Signal Amplification ◽  
Dna Probes ◽  
Electrochemical Aptasensor ◽  
Exonuclease Iii

An electrochemical aptasensor is developed to sensitively detect PDGF-BB based on vanadium disulfide–graphene composites and exonuclease III signal amplification.

scholarly journals SARS-CoV-2 RNA Detection with Duplex-Specific Nuclease Signal Amplification

Micromachines ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 197
Author(s):  
Meiqing Liu ◽  
Haoran Li ◽  
Yanwei Jia ◽  
Pui-In Mak ◽  
Rui P. Martins
Keyword(s):  
Signal Amplification ◽  
Incubation Temperature ◽  
Dna Probes ◽  
Detection Sensitivity ◽  
N Gene ◽  
Rna Detection ◽  
Gold Standard Method ◽  
Complementary Method ◽  
Amplification Method ◽  
Virus Rna

The emergence of the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a zoonotic pathogen, has led to the outbreak of coronavirus disease 2019 (COVID-19) pandemic and brought serious threats to public health worldwide. The gold standard method for SARS-CoV-2 detection requires both reverse transcription (RT) of the virus RNA to cDNA and then polymerase chain reaction (PCR) for the cDNA amplification, which involves multiple enzymes, multiple reactions and a complicated assay optimization process. Here, we developed a duplex-specific nuclease (DSN)-based signal amplification method for SARS-CoV-2 detection directly from the virus RNA utilizing two specific DNA probes. These specific DNA probes can hybridize to the target RNA at different locations in the nucleocapsid protein gene (N gene) of SARS-CoV-2 to form a DNA/RNA heteroduplex. DSN cleaves the DNA probe to release fluorescence, while leaving the RNA strand intact to be bound to another available probe molecule for further cleavage and fluorescent signal amplification. The optimized DSN amount, incubation temperature and incubation time were investigated in this work. Proof-of-principle SARS-CoV-2 detection was demonstrated with a detection sensitivity of 500 pM virus RNA. This simple, rapid, and direct RNA detection method is expected to provide a complementary method for the detection of viruses mutated at the PCR primer-binding regions for a more precise detection.

scholarly journals Turn-On Fluorescence Aptasensor on Magnetic Nanobeads for Aflatoxin M1 Detection Based on an Exonuclease III-Assisted Signal Amplification Strategy

Nanomaterials ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 104
Author(s):  
Fuyuan Zhang ◽  
Linyang Liu ◽  
Shengnan Ni ◽  
Jiankang Deng ◽  
Guo-Jun Liu ◽  
...  
Keyword(s):  
Signal Amplification ◽  
Aflatoxin M1 ◽  
Exonuclease Iii ◽  
Sensor Performance ◽  
Milk Samples ◽  
Increased Sensitivity ◽  
Exo Iii ◽  
Amplification Strategy ◽  
Optimized Conditions ◽  
Magnetic Nanobeads

In order to satisfy the need for sensitive detection of Aflatoxin M1 (AFM1), we constructed a simple and signal-on fluorescence aptasensor based on an autocatalytic Exonuclease III (Exo III)-assisted signal amplification strategy. In this sensor, the DNA hybridization on magnetic nanobeads could be triggered by the target AFM1, resulting in the release of a single-stranded DNA to induce an Exo III-assisted signal amplification, in which numerous G-quadruplex structures would be produced and then associated with the fluorescent dye to generate significantly amplified fluorescence signals resulting in the increased sensitivity. Under the optimized conditions, this aptasensor was able to detect AFM1 with a practical detection limit of 9.73 ng kg−1 in milk samples. Furthermore, the prepared sensor was successfully used for detection of AFM1 in the commercially available milk samples with the recovery percentages ranging from 80.13% to 108.67%. Also, the sensor performance was evaluated by the commercial immunoassay kit with satisfactory results.

An electrochemical aptasensor based on cocoon-like DNA nanostructure signal amplification for the detection of Escherichia coli O157:H7

The Analyst ◽  
2020 ◽  
Vol 145 (22) ◽  
pp. 7340-7348
Author(s):  
Huasong Bai ◽  
Shengjun Bu ◽  
Wensen Liu ◽  
Chengyu Wang ◽  
Zhongyi Li ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Signal Amplification ◽  
Selective Detection ◽  
Escherichia Coli O157 ◽  
Dna Nanostructures ◽  
Electrochemical Aptasensor ◽  
Dna Nanostructure ◽  
Highly Sensitive

We developed an electrochemical aptasensor based on cocoon-like DNA nanostructures as signal tags for highly sensitive and selective detection of Escherichia coli O157:H7.

Sign in / Sign up

Export Citation Format

Share Document