How functional groups influence the ROS generation and cytotoxicity of graphene quantum dots

2017 ◽  
Vol 53 (76) ◽  
pp. 10588-10591 ◽  
Author(s):  
Ya Zhou ◽  
Hanjun Sun ◽  
Faming Wang ◽  
Jinsong Ren ◽  
Xiaogang Qu
Keyword(s):  
Quantum Dots ◽  
Functional Groups ◽  
Graphene Quantum Dots ◽  
Ros Generation ◽  
Hydroxyl Groups ◽  
Carbonyl Groups ◽  
Oxygen Functional Groups

Herein we selectively deactivate the ketonic carbonyl, carboxylic, or hydroxyl groups on GQDs and compare their ROS generation ability. The ROS generation ability of GQDs is closely related to these oxygen functional groups, especially for the ketonic carbonyl groups.

Optimizing oxygen functional groups in graphene quantum dots for improved antioxidant mechanism

2019 ◽  
Vol 21 (3) ◽  
pp. 1336-1343 ◽  
Author(s):  
Yingmin Wang ◽  
Wenhui Kong ◽  
Lifeng Wang ◽  
Jin Zhong Zhang ◽  
Yan Li ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Free Radicals ◽  
Functional Groups ◽  
Graphene Quantum Dots ◽  
Antioxidant Mechanism ◽  
Oxygen Functional Groups

The development of new antioxidants with quick absorbance of free radicals and excellent biocompatibility has drawn intensive attention in recent years.

Ball-Milling Graphite Used for Synthesis of Biocompatible Blue Luminescent Graphene Quantum Dots

2021 ◽  
Vol 6 (2) ◽  
Author(s):  
Zhou J ◽  
◽  
Dong Y ◽  
Ma Y ◽  
Zhang T ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Ball Milling ◽  
Graphene Quantum Dots ◽  
Raw Material ◽  
Hydroxyl Groups ◽  
High Quality ◽  
Widespread Application ◽  
Force Microscopy ◽  
Atomic Force ◽  
Transmission Electron

Graphene Quantum Dots (GQDs) have been prepared by oxidationhydrothermal reaction, using ball-milling graphite as the starting materials. The prepared GQDs are endowed with excellent luminescence properties, with the optimum emission of 320nm. Blue photoluminescent emitted from the GQDs under ultraviolet light. The GQDs are ~3nm in width and 0.5~2 nm in thickness, revealed by high-resolution transmission electron microscopy and atomic force microscopy. In addition, Fourier transform infrared spectrum evidences the existence of carbonyl and hydroxyl groups, meaning GQDs can be dispersed in water easily and used in cellar imaging, and blue area inside L929 cells were clearly observed under the fluorescence microscope. Both low price of raw material and simple prepared method contribute to the high quality GQDs widespread application in future.

scholarly journals Cellular distribution and cytotoxicity of graphene quantum dots with different functional groups

2014 ◽  
Vol 9 (1) ◽  
pp. 108 ◽  
Author(s):  
Xiaochan Yuan ◽  
Zhiming Liu ◽  
Zhouyi Guo ◽  
Yanhong Ji ◽  
Mei Jin ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Functional Groups ◽  
Graphene Quantum Dots ◽  
Cellular Distribution

Influence of Pigment Extraction on Pb(II) Biosorption of Cladophora and Spirogyra Algae Powder

2012 ◽  
Vol 610-613 ◽  
pp. 3591-3598
Author(s):  
Yi Chao Lee ◽  
Shui Ping Chang ◽  
Chih Sheng Lee ◽  
Nien Hsin Kao
Keyword(s):  
Functional Groups ◽  
Binding Sites ◽  
Metal Ion ◽  
Cell Structure ◽  
Extraction Procedure ◽  
Hydroxyl Groups ◽  
Carbonyl Groups ◽  
Pigment Extraction ◽  
The World ◽  
Different Levels

The Cladophora and Spirogyra genera are classified within the green algae division. Species belonging to these genera comprise large filamentous algae, possess significant biomass, and are found in freshwater around the world. These characteristics give Cladophora and Spirogyra high potential to be developed as biological materials. For this study, we harvested fresh Cladophora and Spirogyra and produced algae powder using two of conventional procedures: with pigment extraction and without pigment extraction. The resulting algae powders were subjected to Pb(II) biosorption, and the differences in biosorption rates were subsequently analyzed. Our study found the following: (i) significant differences in cell structure, cell wall thickness, the type and content of cell composition, and the quantity of epiphytes between Cladophora and Spirogyra. This variation influenced the functional groups within the resulting algae powders and their binding sites, which further led to different levels of Pb(II) adsorption. (ii) Glacial acetic acid, a compound commonly employed in pigment extraction procedures, affected the functional groups and the binding sites of the resulting algae powders. For Cladophora algae powder, Pb(II) biosorption was reduced by 16.6 %; whereas for Spirogyra algae powder, Pb(II) biosorption was reduced by 19.8 %. (iii) The pigment extraction procedure exerted the most significant influence on the carbonyl groups and hydroxyl groups in algae powder. (iv) The pigment extraction procedure is not suitable for the preparation of algae powders which will be used for metal ion biosorption.

scholarly journals Quantum Yield Enhancement in Graphene Quantum Dots via Esterification with Benzyl Alcohol

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Suzuka Tachi ◽  
Hiroki Morita ◽  
Misaki Takahashi ◽  
Yusuke Okabayashi ◽  
Takuya Hosokai ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Quantum Yield ◽  
Benzyl Alcohol ◽  
Functional Groups ◽  
Photophysical Properties ◽  
Graphene Quantum Dots ◽  
Yield Enhancement ◽  
Light Illumination ◽  
Nonradiative Recombination ◽  
Widespread Application

Abstract The quantum yield of graphene quantum dots was enhanced by restriction of the rotation and vibration of surface functional groups on the edges of the graphene quantum dots via esterification with benzyl alcohol; this enhancement is crucial for the widespread application of graphene quantum dots in light-harvesting devices and optoelectronics. The obtained graphene quantum dots with highly graphene-stacked structures are understood to participate in π–π interactions with adjacent aromatic rings of the benzylic ester on the edges of the graphene quantum dots, thus impeding the nonradiative recombination process in graphene quantum dots. Furthermore, the crude graphene quantum dots were in a gel-like solid form and showed white luminescence under blue light illumination. Our results show the potential for improving the photophysical properties of nanomaterials, such as the quantum yield and band-gap energy for emission, by controlling the functional groups on the surface of graphene quantum dots through an organic modification approach.

scholarly journals Understanding of Catalytic ROS Generation From Defect-Rich Graphene Quantum-Dots for Therapeutic Effects in Tumor Microenvironment

2021 ◽  
Author(s):  
Xichu Wang ◽  
Chuangang Hu ◽  
Zi (Sophia) Gu ◽  
Liming Dai
Keyword(s):  
Quantum Dots ◽  
Tumor Microenvironment ◽  
Catalytic Mechanism ◽  
Defect Density ◽  
Low Cost ◽  
Graphene Quantum Dots ◽  
Catalytic Efficiency ◽  
Catalytic Performance ◽  
Ros Generation ◽  
Therapeutic Effects

Abstract Owing to their low cost, high catalytic efficiency and biocompatibility, carbon-based metalfree catalysts (C-MFCs) have attracted intense interest for various applications, ranging from energy through environmental to biomedical technologies. While considerable efforts and progress have been made in mechanistic understanding of C-MFCs for non-biomedical applications, their catalytic mechanism for therapeutic effects has rarely been investigated. In this study, defect-rich graphene quantum dots (GQDs) were developed as C-MFCs for efficient ROS generation, specifically in the H2O2 -rich tumor microenvironment to cause multi-level damage of subcellular components (even in nuclei). While a desirable anti-cancer performance was achieved, the catalytic performance was found to strongly depend on the defect density. It is for the first time that the defect-induced catalytic generation of ROS by C-MFCs in the tumor microenvironment was demonstrated and the associated catalytic mechanism was elucidated. This work opens a new avenue for the development of safe and efficient catalytic nanomedicine.

Folic acid-functionalized graphene quantum dots with tunable fluorescence emission for cancer cell imaging and optical detection of Hg2+

2018 ◽  
Vol 42 (6) ◽  
pp. 4352-4360 ◽  
Author(s):  
Ruiyi Li ◽  
Xuan Wang ◽  
Zaijun Li ◽  
Haiyan Zhu ◽  
Junkang Liu
Keyword(s):  
Quantum Dots ◽  
Folic Acid ◽  
Functional Groups ◽  
Cancer Cell ◽  
Cell Imaging ◽  
Optical Detection ◽  
Graphene Quantum Dots ◽  
Fluorescence Emission ◽  
Electrical Characteristics ◽  
Functionalized Graphene

Functional groups may alter the optical and electrical characteristics of graphene quantum dots and lead to unusual properties and related applications.

Insight into the effect of functional groups on visible-fluorescence emissions of graphene quantum dots

2016 ◽  
Vol 4 (11) ◽  
pp. 2235-2242 ◽  
Author(s):  
Jianglin Du ◽  
Haiyu Wang ◽  
Lei Wang ◽  
Shoujun Zhu ◽  
Yubin Song ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Functional Groups ◽  
Graphene Quantum Dots ◽  
Light Emitting ◽  
Insight Into

Various functional groups in graphene quantum dots may play critical roles in their fluorescent emissions, and different groups contribute to different light-emitting wavelengths.

Nitrogen-Doped Graphene Quantum Dots with Oxygen-Rich Functional Groups

2011 ◽  
Vol 134 (1) ◽  
pp. 15-18 ◽  
Author(s):  
Yan Li ◽  
Yang Zhao ◽  
Huhu Cheng ◽  
Yue Hu ◽  
Gaoquan Shi ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Functional Groups ◽  
Graphene Quantum Dots ◽  
Nitrogen Doped ◽  
Nitrogen Doped Graphene ◽  
Doped Graphene
Sign in / Sign up

Export Citation Format

Share Document