Fluorescent Carbon Dots and their Applications in Sensing of Small Organic Molecules

Background: Fluorescence-based sensing is considered highly sensitive and fluorescent probes with improved properties are always desired. Fluorescent carbon dots (CDs) are newly emerging quasi-spherical nanoparticles of less than 10 nm in size and belong to the carbon nano-material’s family. CDs have great potential as fluorescent probes and currently are under open deliberation by the researchers due to their striking properties such as low environmental hazard, high selectivity, greater sensitivity, good biocompatibility, tunable fluorescent properties and excitation dependent multicolor emission behavior. Introduction: This review demonstrates various available methods for fabrication of fluorescent CDs, capping of CDs and characterization with various techniques including UV-visible, FT-IR, and TEM. Analytical applications using CDs for the sensing of small organic molecules, specifically nitroaromatic compounds in the environmental samples are complied. Methods: The review covers literature related to synthesis and characterization of carbon dots. It includes around 171 research articles in this field. Results: Carbon dots can be synthesized using numerous routes. In all cases CDs possess spectral properties with little variation in wavelength maxima. Optical properties of CDs can be tuned by compositing these with metallic quantum dots or by modifying their surface with desired functionalities. HR-TEM is needed to see the morphology and size of particles whereas UV-Visible and FTIR are indispensable tools for this kind of research. These particles are successfully applied to sense small molecules in some matrices. Conclusion: Carbon dots are bright stars in fluorescent sensing of small molecules. However, more research is needed to determine small organic molecules in diversified areas of analysis.

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Electrospinning Highly Concentrated Sodium Alginate Nanofibres without Surfactants by Adding Fluorescent Carbon Dots

Nanomaterials ◽

10.3390/nano10030565 ◽

2020 ◽

Vol 10 (3) ◽

pp. 565 ◽

Cited By ~ 2

Author(s):

Junke Yu ◽

Zhihui Zhao ◽

Jianxin Sun ◽

Cunzhen Geng ◽

Qingxu Bu ◽

...

Keyword(s):

Electron Microscopy ◽

Sodium Alginate ◽

Carbon Dots ◽

In Vitro Cytotoxicity ◽

Fluorescent Properties ◽

Cytotoxicity Assessment ◽

Fluorescent Carbon Dots ◽

Scanning Electron ◽

Fluorescent Carbon

In this study, sodium alginate (SA) nanofibres were obtained by electrospinning via the assistance of traditional poly(ethyl oxide) (PEO) and dimethyl sulfoxide (DMSO) with a high SA/PEO ratio of up to 94:6. However, surfactants with more or less toxicities were replaced by nontoxic and fluorescent carbon dots (CDs) to improve spinnability. Experimental details were conducted by fixing the ratio of SA/PEO to 90:10. Then, the electrospinning products of solutions with different compositions were observed with scanning electron microscopy. Properties such as conductivity, surface tension and rheology of the solutions were investigated to determine the key influencing factors. Moreover, since CDs have excellent fluorescence properties, the fluorescent properties of the nanofibre membrane that was blended with CDs were then collected. In addition, in vitro cytotoxicity assessment of the nanofibres were conducted to evaluate the toxicities and biocompatibility.

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Fluorescent Carbon Dots for Sensing Metal Ions and Small Molecules

Chinese Journal of Analytical Chemistry ◽

10.1016/j.cjac.2021.09.005 ◽

2021 ◽

Author(s):

XU Xiang-Jun ◽

GE Sheng ◽

LI Dong-Qin ◽

XU Zi-Qiang ◽

Wang Er-Jing ◽

...

Keyword(s):

Metal Ions ◽

Small Molecules ◽

Carbon Dots ◽

Fluorescent Carbon Dots ◽

Fluorescent Carbon

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Lighting up Individual Organelles With Fluorescent Carbon Dots

Frontiers in Chemistry ◽

10.3389/fchem.2021.784851 ◽

2021 ◽

Vol 9 ◽

Author(s):

Haifang Liu ◽

Jiancheng Guo ◽

Aaron Albert Aryee ◽

Linlin Hua ◽

Yuanqiang Sun ◽

...

Keyword(s):

Small Molecules ◽

Fluorescent Probes ◽

Targeted Drug Delivery ◽

Carbon Dots ◽

High Selectivity ◽

Golgi Body ◽

Normal Functioning ◽

Cell Organelles ◽

Low Cytotoxicity ◽

Fluorescent Carbon Dots

Cell organelles play crucial roles in the normal functioning of an organism, therefore the disruption of their operation is associated with diseases and in some cases death. Thus, the detection and monitoring of the activities within these organelles are of great importance. Several probes based on graphene oxide, small molecules, and other nanomaterials have been developed for targeting specific organelles. Among these materials, organelle-targeted fluorescent probes based on carbon dots have attracted substantial attention in recent years owing to their superior characteristics, which include facile synthesis, good photostability, low cytotoxicity, and high selectivity. The ability of these probes to target specific organelles enables researchers to obtain valuable information for understanding the processes involved in their functions and/or malfunctions and may also aid in effective targeted drug delivery. This review highlights recently reported organelle-specific fluorescent probes based on carbon dots. The precursors of these carbon dots are also discussed because studies have shown that many of the intrinsic properties of these probes originate from the precursor used. An overview of the functions of the discussed organelles, the types of probes used, and their advantages and limitations are also provided. Organelles such as the mitochondria, nucleus, lysosomes, and endoplasmic reticulum have been the central focus of research to date, whereas the Golgi body, centrosome, vesicles, and others have received comparatively little attention. It is therefore the hope of the authors that further studies will be conducted in an effort to design probes with the ability to localize within these less studied organelles so as to fully elucidate the mechanisms underlying their function.

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Nitrogen-doped carbon dots from Hutai-8 grape skin and their application in Hg2+ detection

Current Nanoscience ◽

10.2174/1573413716999200819201126 ◽

2020 ◽

Vol 16 ◽

Author(s):

Pan Zhang ◽

Shun-Sheng Zhao ◽

JiaJia Wang ◽

Xiang Rong Liu

Keyword(s):

Heavy Metal ◽

Carbon Source ◽

Fluorescence Quenching ◽

Hydrothermal Method ◽

Water Samples ◽

Carbon Dots ◽

Mercury Ions ◽

Grape Skin ◽

Fluorescent Carbon Dots ◽

Fluorescent Carbon

Background: In recent years, environmental pollution and heavy metal pollution caused by rapid urbanization and industrialization have become increasingly serious. Among them, mercury (II) ion (Hg2+) is one of the highly toxic heavy metal ions, and its pollution comes from various natural resources and human activities. Therefore, people attach great importance to the development of analytical methods for effective analysis and sensitive detection of Hg2+ . Objective: Using grape skin as a green and environmental friendly carbon source, to synthesize fluorescent carbon dots, and try to apply them to the detect the concentration of Hg2+ in water. Method: Using "Hutai No. 8" grape skin as carbon source, fluorescent carbon dots were synthesized by one-step hydrothermal method. Structure and fluorescent properties of the carbon dots were tested using TEM, XPS, XRD and other characterization instruments, and their utilization on detection of mercury ions in the actual water samples was explored. Results: The CDs had a particle size of about 4.8 nm and a spherical shape. There are N-H, C-N, C=O and other functional groups on the surface. It was found that Hg2+ has obvious fluorescence quenching effect on CDs, and thus CDs fluorescence quenching method to detect the concentration Hg2+ was established, and the detection limit is 3.7 μM, which could be applied to test the concentration of Hg2+ in water samples. Conclusion: Using grape skin as carbon source, fluorescent carbon dots were successfully synthesized by hydrothermal method. Carbon dots were used to detect mercury ions in water, and a method for detecting mercury ions in actual water samples was established.

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Anti-counterfeiting application of fluorescent carbon dots derived from wasted coffee grounds

Optik ◽

10.1016/j.ijleo.2021.166449 ◽

2021 ◽

pp. 166449

Author(s):

Woo Tae Hong ◽

Jin Young Park ◽

Jong Won Chung ◽

Hyun Kyoung Yang ◽

Jae-Yong Je

Keyword(s):

Carbon Dots ◽

Coffee Grounds ◽

Fluorescent Carbon Dots ◽

Fluorescent Carbon

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Carbon dots derived from Fusobacterium nucleatum for intracellular determination of Fe3+ and bioimaging both in vitro and in vivo

Analytical Methods ◽

10.1039/d1ay00020a ◽

2021 ◽

Author(s):

Lijuan Liu ◽

Shengting Zhang ◽

Xiaodan Zheng ◽

Hongmei Li ◽

Qi Chen ◽

...

Keyword(s):

Carbon Dots ◽

Fusobacterium Nucleatum ◽

Living Cells ◽

First Time ◽

Fluorescent Carbon Dots ◽

Fluorescent Carbon

Fusobacterium nucleatum has been employed for the first time to synthesize fluorescent carbon dots which could be applied for the determination of Fe3+ ions in living cells and bioimaging in vitro and in vivo with excellent biocompatibility.

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