Understanding of catalytic ROS generation from defect-rich graphene quantum-dots for therapeutic effects in tumor microenvironment

AbstractOwing to their low cost, high catalytic efficiency and biocompatibility, carbon-based metal-free catalysts (C-MFCs) have attracted intense interest for various applications, ranging from energy through environmental to biomedical technologies. While considerable effort 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 damages 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.

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

10.21203/rs.3.rs-657051/v1 ◽

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.

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Investigation into the Catalytic Performance of Cu(II) Supported Graphene Quantum Dots Modified NiFe2O4 as a Proficient Nano-Catalyst in the Synthesis of Propargylasmines

Catalysis Letters ◽

10.1007/s10562-020-03400-y ◽

2020 ◽

Author(s):

Soudabeh Monajjemifar ◽

Farid Moeinpour ◽

Fatemeh S. Mohseni-Shahri

Keyword(s):

Quantum Dots ◽

Graphene Quantum Dots ◽

Catalytic Performance ◽

Nano Catalyst

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High yield synthesis of graphene quantum dots from biomass waste as a highly selective probe for Fe3+ sensing

Scientific Reports ◽

10.1038/s41598-020-78070-2 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Aumber Abbas ◽

Tanveer A. Tabish ◽

Steve J. Bull ◽

Tuti Mariana Lim ◽

Anh N. Phan

Keyword(s):

Quantum Dots ◽

Optical Properties ◽

Low Cost ◽

Graphene Quantum Dots ◽

Cost Effective ◽

Renewable Resource ◽

Microwave Treatment ◽

High Yield ◽

Biomass Waste ◽

Practical Applications

AbstractGraphene quantum dots (GQDs), a novel type of zero-dimensional fluorescent materials, have gained considerable attention owing to their unique optical properties, size and quantum confinement. However, their high cost and low yield remain open challenges for practical applications. In this work, a low cost, green and renewable biomass resource is utilised for the high yield synthesis of GQDs via microwave treatment. The synthesis approach involves oxidative cutting of short range ordered carbon derived from pyrolysis of biomass waste. The GQDs are successfully synthesised with a high yield of over 84%, the highest value reported to date for biomass derived GQDs. As prepared GQDs are highly hydrophilic and exhibit unique excitation independent photoluminescence emission, attributed to their single-emission fluorescence centre. As prepared GQDs are further modified by simple hydrothermal treatment and exhibit pronounced optical properties with a high quantum yield of 0.23. These modified GQDs are used for the highly selective and sensitive sensing of ferric ions (Fe3+). A sensitive sensor is prepared for the selective detection of Fe3+ ions with a detection limit of as low as 2.5 × 10–6 M. The utilisation of renewable resource along with facile microwave treatment paves the way to sustainable, high yield and cost-effective synthesis of GQDs for practical applications.

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Graphene Quantum Dots Open Up New Prospects for Interfacial Modifying in Graphene/Silicon Schottky Barrier Solar Cell

Energy Material Advances ◽

10.34133/2021/8481915 ◽

2021 ◽

Vol 2021 ◽

pp. 1-11

Author(s):

Chao Geng ◽

Xiuhua Chen ◽

Shaoyuan Li ◽

Zhao Ding ◽

Wenhui Ma ◽

...

Keyword(s):

Quantum Dots ◽

Particle Size ◽

Schottky Barrier ◽

Low Cost ◽

Graphene Quantum Dots ◽

Separation Processes ◽

Band Bending ◽

Carrier Recombination ◽

Photovoltaic Applications ◽

Graphene Oxide Quantum Dots

Graphene/silicon (Gr/Si) Schottky barrier solar cells (SBSCs) are attractive for harvesting solar energy and have been gaining grounds for its low-cost solution-processing. The interfacial barrier between graphene and silicon facilitates the reducing excessive carrier recombination while accelerating the separation processes of photo-generated carriers at the interface, which empowers the performance of Gr/Si SBSCs. However, the difficulty to control the interface thickness prevents its application. Here, we introduce the graphene oxide quantum dots (GOQDs) as a unique interfacial modulation species with tunable thickness by controlling the GOQDs particle size. The power conversion efficiency (PCE) of 13.67% for Gr/Si-based SBSC with outstanding stability in the air is obtained with the optimal barrier thickness (26 nm) and particle size (4.15 nm) of GOQDs. The GOQDs in Gr/Si-based SBSCs provide the extra band bending which further enhances the PCE for its photovoltaic applications.

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Graphene quantum dots as a novel sensing material for low-cost resistive and fast-response humidity sensors

Sensors and Actuators B Chemical ◽

10.1016/j.snb.2015.04.092 ◽

2015 ◽

Vol 218 ◽

pp. 73-77 ◽

Cited By ~ 31

Author(s):

Virginia Ruiz ◽

Iván Fernández ◽

Pedro Carrasco ◽

Germán Cabañero ◽

Hans J. Grande ◽

...

Keyword(s):

Quantum Dots ◽

Low Cost ◽

Graphene Quantum Dots ◽

Fast Response ◽

Humidity Sensors ◽

Sensing Material

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

Chemical Communications ◽

10.1039/c7cc04831a ◽

2017 ◽

Vol 53 (76) ◽

pp. 10588-10591 ◽

Cited By ~ 33

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.

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Ultrasonic-assisted recycling of Nile tilapia fish scale biowaste into low-cost nano-hydroxyapatite: Ultrasonic-assisted adsorption for Hg2+ removal from aqueous solution followed by “turn-off” fluorescent sensor based on Hg2+-graphene quantum dots

Ultrasonics Sonochemistry ◽

10.1016/j.ultsonch.2020.104966 ◽

2020 ◽

Vol 63 ◽

pp. 104966 ◽

Cited By ~ 5

Author(s):

Phitchan Sricharoen ◽

Nunticha Limchoowong ◽

Prawit Nuengmatcha ◽

Saksit Chanthai

Keyword(s):

Aqueous Solution ◽

Quantum Dots ◽

Nile Tilapia ◽

Fluorescent Sensor ◽

Low Cost ◽

Graphene Quantum Dots ◽

Fish Scale ◽

Ultrasonic Assisted

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Preparation of AuNPs/GQDs/SiO2 Composite and Its Catalytic Performance in Oxidation of Veratryl Alcohol

Journal of Nanomaterials ◽

10.1155/2017/4130569 ◽

2017 ◽

Vol 2017 ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

Yaoyao Yang ◽

Jiali Zhang ◽

Fangwei Zhang ◽

Shouwu Guo

Keyword(s):

Quantum Dots ◽

Gold Nanoparticles ◽

Catalytic Activity ◽

Silicon Dioxide ◽

Graphene Quantum Dots ◽

Veratryl Alcohol ◽

Catalytic Performance ◽

Amide Bond ◽

Amino Group ◽

Reaction Systems

Composites of gold nanoparticles and graphene quantum dots (AuNPs/GQDs) exhibit excellent dispersibility in aqueous solutions. Thus, it is difficult to separate them from wet reaction systems when they are used as catalysts. To resolve this issue, in this study, an AuNPs/GQDs composite was immobilized on silicon dioxide through the hydrothermal method, which involved the formation of an amide bond between the surface GQDs of the AuNPs/GQDs composite and the amino group of the silane. The as-synthesized AuNPs/GQDs/SiO2 composite was found to be suitable for use as a heterogeneous catalyst for the oxidation of veratryl alcohol in water and exhibited catalytic activity comparable to that of bare AuNPs/GQDs as well as better recyclability.

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