H2O2-mediated fluorescence quenching of double-stranded DNA templated copper nanoparticles for label-free and sensitive detection of glucose

In the condition of 1.24 mmol/L EDTANa2, 16.7 mmol/L NaCl and 0.17 mmol/L Tris, the substrate chain of double-stranded DNA (dsDNA) could be cracked by Pb2+ to release single-stranded DNA (ssDNA) that adsorb onto AuPd nanoparticle (AuPdNP) and form stable AuPdNP-ssDNA, but the dsDNA can not protect AuPdNP that were aggregated to big AuPdNP aggregations (AuPdNPA) under the action of NaCl. The AuPdNP-ssDNA and AuPdNPA could be separated by centrifugation. With the concentration of Pb2+ increased, the released ssDNA increased, the AuPdNP-ssDNA in centrifugation solution increased and the catalytic effect enhanced on the fluorescence quenching reaction of Rhodamine 6G (Rh6G) and NaH2PO2, which led the fluorescence intensity at 552nm to decrease. The decreased fluorescence intensity (ΔF552nm) was linear to the concentration of Pb2+ in the range of 0.33-8.00 nmol/L, a detection limit of 0.21 nmol/L. The proposed method was applied to detect Pb2+ in water samples, with satisfactory results.

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Label-Free Sensitive Detection of Steroid Hormone Cortisol Based on Target-Induced Fluorescence Quenching of Quantum Dots

Langmuir ◽

10.1021/acs.langmuir.0c00513 ◽

2020 ◽

Vol 36 (27) ◽

pp. 7781-7788

Author(s):

Ye Liu ◽

Bo Wu ◽

Ekembu K. Tanyi ◽

Sanjida Yeasmin ◽

Li-Jing Cheng

Keyword(s):

Quantum Dots ◽

Fluorescence Quenching ◽

Steroid Hormone ◽

Sensitive Detection ◽

Label Free

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Inhibition of double-stranded DNA templated copper nanoparticles as label-free fluorescent sensors for l-histidine detection

New Journal of Chemistry ◽

10.1039/c5nj01847a ◽

2015 ◽

Vol 39 (11) ◽

pp. 8896-8900 ◽

Cited By ~ 22

Author(s):

Hai-Bo Wang ◽

Hong-Ding Zhang ◽

Ying Chen ◽

Yan-Ming Liu

Keyword(s):

Copper Nanoparticles ◽

Fluorescent Sensors ◽

Label Free ◽

Fluorescent Sensing ◽

Double Stranded Dna

A label-free fluorescent sensing strategy was reported for l-histidine detection by the inhibition of double-stranded DNA templated copper nanoparticles.

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Label-free and sensitive detection of Ochratoxin A based on dsDNA-templated copper nanoparticles and exonuclease-catalyzed target recycling amplification

The Analyst ◽

10.1039/c8an00158h ◽

2018 ◽

Vol 143 (8) ◽

pp. 1829-1834 ◽

Cited By ~ 17

Author(s):

Chunxia Song ◽

Wenwen Hong ◽

Xiaoyu Zhang ◽

Ying Lu

Keyword(s):

Ochratoxin A ◽

Copper Nanoparticles ◽

Sensitive Detection ◽

Label Free ◽

Target Recycling ◽

Recycling Amplification ◽

Sensitive Method

A sensitive method for Ochratoxin A detection was developed which combines the advantages of label-free dsDNA-templated copper nanoparticles and exonuclease-catalyzed recycling amplification.

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A Label-Free Fluorescent Sensor Based on the Formation of Poly(thymine)-Templated Copper Nanoparticles for the Sensitive and Selective Detection of MicroRNA from Cancer Cells

Chemosensors ◽

10.3390/chemosensors8030052 ◽

2020 ◽

Vol 8 (3) ◽

pp. 52

Author(s):

Qian Ma ◽

Zhiqiang Gao ◽

Hiranya Dayal ◽

Sam Fong Yau Li

Keyword(s):

Cancer Cells ◽

Copper Nanoparticles ◽

Fluorescent Sensor ◽

Rolling Circle Amplification ◽

High Specificity ◽

Excitation Wavelength ◽

Selective Detection ◽

Label Free ◽

Rolling Circle ◽

Highly Sensitive

In this work, a simple and label-free fluorescence “off” to “on” platform was designed for the sensitive and selective detection of microRNA (miRNA) in cancer cells. This method utilized a padlock DNA-based rolling circle amplification (P-RCA) to synthesize fluorescent poly(thymine) (PolyT) which acted as a template for the synthesis of copper nanoparticles (CuNPs) within 10 minutes under mild conditions. While the repeated PolyT sequence was used as the template for CuNP synthesis, other non-PolyT parts (single strand-DNAs without the capacity to act as the template for CuNP formation) served as “smart glues” or rigid linkers to build complex nanostructures. Under the excitation wavelength of 340 nm, the synthesized CuNPs emitted strong red fluorescence effectively at 620 nm. To demonstrate the use of this method as a universal biosensor platform, lethal-7a (let-7a) miRNA was chosen as the standard target. This sensor could achieve highly sensitive and selective detection of miRNA in the presence of other homologous analogues for the combination of P-RCA with the fluorescent copper nanoparticle. Overall, this novel label-free method holds great potential in the sensitive detection of miRNA with high specificity in real samples.

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