Ratiometric fluorescence sensor based on carbon dots as internal reference signal and T7 exonuclease-assisted signal amplification strategy for microRNA-21 detection

Abstract Background Protein tyrosine kinase 7 (PTK 7) is a membrane receptor, which can be found in various kinds of cancers. In view of this, detection of PTK 7 in the peripheral circulation would be an effective way for the early diagnosis of cancer. Results In this work, a multi-carbon dots and aptamer-based signal amplification ratiometric fluorescence probe was developed. The fluorescence of the aptamer-modified y-CDs and b-CDs were respectively chosen as the detection signal and interior label. The fluorescence of y-CDs was quenched by Fe3O4 and cDNA (complement to aptamer) compound without PTK 7, but recovered by the addition of PTK 7. Then, the free aptamer was cut by DNase I, which amplified the detection signal. The ratiometric fluorescence sensor for PTK 7 was established with the LOD of 0.016 ng mL−1. Conclusions Summary, a multi-carbon dots and aptamer-based signal amplification ratiometric fluorescence probe was developed for the detection of protein tyrosine kinase 7. The developed probe was applied to PTK 7 detection in MCF-7 cells and human serum with satisfying results, thus indicating that this probe has huge potential in clinical practice.

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Nanozyme Sensor Array Plus Solvent-Mediated Signal Amplification Strategy for Ultrasensitive Ratiometric Fluorescence Detection of Exosomal Proteins and Cancer Identification

Analytical Chemistry ◽

10.1021/acs.analchem.1c02010 ◽

2021 ◽

Author(s):

Meng-Xian Liu ◽

He Zhang ◽

Xue-Wei Zhang ◽

Shuai Chen ◽

Yong-Liang Yu ◽

...

Keyword(s):

Fluorescence Detection ◽

Signal Amplification ◽

Sensor Array ◽

Ratiometric Fluorescence ◽

Amplification Strategy

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A ratiometric fluorescence sensor based on UiO-66-CdTe@ZIF-8 core-shell nanocomposites for the highly selective detection of NO

10.21203/rs.3.rs-891851/v1 ◽

2021 ◽

Author(s):

Hailan Shi ◽

Li Zhang

Keyword(s):

Quantum Dots ◽

Solvothermal Method ◽

Reference Signal ◽

Fluorescence Sensor ◽

Core Shell ◽

Selective Detection ◽

Biological Applications ◽

Ratiometric Fluorescence ◽

Zeolitic Imidazolate Framework ◽

Large Molecules

Abstract In this work, a ratiometric fluorescence sensor based on UiO-66-CdTe@ZIF-8 core-shell nanocomposites (CSNCPs) was developed for the highly selective detection of NO. The yellow-emitting UiO-66-NH2 core was synthesised using the solvothermal method and then coated with red-emitting CdTe quantum dots (QDs). The resulting core UiO-66-CdTe nanocomposites served as the signal-displaying unit (UiO-66-CdTe). Next, the UiO-66-CdTe nanocomposite was encapsulated in a zeolitic imidazolate framework (ZIF-8), whereas large molecules such as substrate and oxidase have very little effect on its fluorescence. A detectable signal was obtained by monitoring the NO quenching fluorescence of UiO-66-NH2, and the CdTe QDs served as the reference signal. The fluorescence quenching ratio I442/I574 was proportional to the logarithm of NO concentration concentration in the range of 0-0.10 nM with the detection limit of 0.11 nM. The results demonstrate that the proposed UiO-66-CdTe@ZIF-8 CSNCPs-based sensor is suitable for quantitative purposes in various environmental and biological applications.

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A ratiometric fluorescence sensor for triticonazole based on the encapsulated boron-doped and phosphorous-doped carbon dots in the metal organic framework

Spectrochimica Acta Part A Molecular and Biomolecular Spectroscopy ◽

10.1016/j.saa.2020.118951 ◽

2021 ◽

Vol 246 ◽

pp. 118951 ◽

Cited By ~ 1

Author(s):

Roghayeh Shokri ◽

Mohammad Amjadi

Keyword(s):

Carbon Dots ◽

Metal Organic Framework ◽

Fluorescence Sensor ◽

Ratiometric Fluorescence ◽

Boron Doped ◽

Metal Organic ◽

Doped Carbon Dots ◽

Organic Framework

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A colorimetric paper sensor for visual detection of mercury ions constructed with dual-emission carbon dots

New Journal of Chemistry ◽

10.1039/c8nj03683g ◽

2018 ◽

Vol 42 (19) ◽

pp. 15671-15677 ◽

Cited By ~ 8

Author(s):

Yifan Wang ◽

Liang Yang ◽

Bianhua Liu ◽

Shaoming Yu ◽

Changlong Jiang

Keyword(s):

Carbon Dots ◽

Visual Detection ◽

Mercury Ions ◽

Ratiometric Fluorescence ◽

Blue Fluorescence ◽

Internal Reference ◽

Dual Emission ◽

Paper Sensor ◽

Fluorescent Carbon Dots ◽

Fluorescent Carbon

A ratiometric fluorescence nanosensor has been developed by mixing blue fluorescent carbon dots and red fluorescent carbon dots, where the blue fluorescence can be selectively quenched by Hg2+, while the red fluorescence is an internal reference.

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