Graphene derivatives: graphane, fluorographene, graphene oxide, graphyne and graphdiyne

Nano-materials based drug delivery modalities to specific organs and tissues has become one of the critical endeavors in pharmaceutical research. Recently, two-dimensional graphene has elicited considerable research interest because of its potential application in drug delivery systems. Here we report, the drug delivery applications of PEGylated nano-graphene oxide (nGO-PEG), complexed with a multiphoton active and anti-cancerous diarylheptanoid drug curcumin. Specifically, graphene-derivatives were used as nanovectors for the delivery of the hydrophobic anticancer drug curcumin due to its high surface area and easy surface functionalization. nGO was synthesized by modified Hummer’s method and confirmed by XRD analysis. The formation of nGO, nGO-PEG and nGO-PEG-Curcumin complex were monitored through UV-vis, IR spectroscopy. MTT assay and AO/EB staining found that nGO-PEG-Curcumin complex afforded highly potent cancer cell killing in vitro with a human breast cancer cell line MCF7.

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Versatile Graphene Oxide Nanosheets via Covalent Functionalization and Their Applications

Materials Chemistry Frontiers ◽

10.1039/d1qm00066g ◽

2021 ◽

Author(s):

Minju Park ◽

Namhee Kim ◽

Jiyoung Lee ◽

Minsu Gu ◽

Byeong-Su Kim

Keyword(s):

Graphene Oxide ◽

Two Dimensional ◽

Graphene Oxide Nanosheets ◽

Covalent Functionalization ◽

Graphene Derivatives

Even though many graphene derivatives that are atomically thin two-dimensional structures, such as graphene oxide (GO), have triggered enormous interest in the scientific and industrial communities owing to their easy...

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Investigation of Graphene Derivatives on Electrical Properties of Alkali Activated Slag Composites

Materials ◽

10.3390/ma14164374 ◽

2021 ◽

Vol 14 (16) ◽

pp. 4374

Author(s):

Wu-Jian Long ◽

Xuanhan Zhang ◽

Biqin Dong ◽

Yuan Fang ◽

Tao-Hua Ye ◽

...

Keyword(s):

Graphene Oxide ◽

Electrical Properties ◽

Mechanical Performance ◽

Structural Defects ◽

Alkali Activated Slag ◽

Mechanical And Electrical Properties ◽

Reduced Graphene ◽

Graphene Derivatives ◽

Activated Slag ◽

Alkali Activated

Reduced graphene oxide (rGO) has been widely used to modify the mechanical performance of alkali activated slag composites (AASC); however, the mechanism is still unclear and the electrical properties of rGO reinforced AASC are unknown. Here, the rheological, mechanical, and electrical properties of the AASC containing rGO nanosheets (0, 0.1, 0.2, and 0.3 wt.%) are investigated. Results showed that rGO nanosheets addition can significantly improve the yield stress, plastic viscosity, thixotropy, and compressive strength of the AASC. The addition of 0.3 wt.% rGO nanosheets increased the stress, viscosity, thixotropy, and strength by 186.77 times, 3.68 times, 15.15 times, and 21.02%, respectively. As for electrical properties, the impedance of the AASC increased when the rGO content was less than 0.2 wt.% but decreased with the increasing dosage. In contrast, the dielectric constant and electrical conductivity of the AASC containing rGO nanosheets decreased and then increased, which can be attributed to the abundant interlayer water and the increasing structural defects as the storage sites for charge carriers, respectively. In addition, the effect of graphene oxide (GO) on the AASC is also studied and the results indicated that the agglomeration of GO nanosheets largely inhibited the application of it in the AASC, even with a small dosage.

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Structural and vibrational study of graphene oxide via coronene based models: theoretical and experimental results

Materials Research Express ◽

10.1088/2053-1591/3/5/055020 ◽

2016 ◽

Vol 3 (5) ◽

pp. 055020 ◽

Cited By ~ 11

Author(s):

João Paulo Almeida de Mendonça ◽

Alessandro Henrique de Lima ◽

Georgia Maria Amaral Junqueira ◽

Welber Gianini Quirino ◽

Cristiano Legnani ◽

...

Keyword(s):

Graphene Oxide ◽

Experimental Results ◽

Vibrational Study

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Potentiometric Taste Sensing Using Reduced Graphene Oxide Screen Printed Electrodes

Sensor Letters ◽

10.1166/sl.2020.4302 ◽

2020 ◽

Vol 18 (12) ◽

pp. 881-888

Author(s):

Anil B. Patil ◽

Umesh. J. Tupe ◽

Vikas V. Deshmane ◽

Arun V. Patil

Keyword(s):

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Principal Component ◽

Experimental Results ◽

Statistical Tool ◽

Sensing Applications ◽

Screen Printed Electrodes ◽

Reduced Graphene ◽

Pharmaceutical Industries ◽

Screen Printed

This paper reports the development of simple and economical reduced graphene oxide (rGO) based screen-printed electrodes (SPE) for five basic taste sensing applications. Twenty different test solutions for the five tastes of salty, sour, sweet, umami, and bitter at 1 ppm, 10 ppm, 100 ppm, 1000 ppm concentration levels were tested with the fabricated SPEs. From experimental results, electrical signals generated between the electrode and test solution interface were measured using the potentiometric method. Satisfactory potentiometric responses of SPEs to different ppm concentrations for each sample were used to analyze the sample data. Histogram using the statistical tool was used to analyze the changes in the conductivity response. A multivariate Principal Component Analysis (PCA) statistical tool correlated using loading plots between variables and factors of all the five basic tastes. The plot showed the interrelation between variables and test samples. The obtained experimental results from these rGO based SPEs make them suitable for their use in taste sensing applications such as for any taste disorder disability, food-producing industry, pharmaceutical industries, etc.

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Gradient Chitosan Hydrogels Modified with Graphene Derivatives and Hydroxyapatite: Physiochemical Properties and Initial Cytocompatibility Evaluation

International Journal of Molecular Sciences ◽

10.3390/ijms21144888 ◽

2020 ◽

Vol 21 (14) ◽

pp. 4888

Author(s):

Karolina Kosowska ◽

Patrycja Domalik-Pyzik ◽

Małgorzata Sekuła-Stryjewska ◽

Sylwia Noga ◽

Joanna Jagiełło ◽

...

Keyword(s):

Graphene Oxide ◽

Photoelectron Spectroscopy ◽

Mechanical Analysis ◽

Biological Properties ◽

Human Umbilical Cord ◽

Tissue Engineering Scaffolds ◽

X Ray ◽

Chitosan Matrix ◽

Graphene Derivatives

In this study, we investigated preparation of gradient chitosan-matrix hydrogels through a novel freezing–gelling–thawing method. The influence of three types of graphene family materials (GFM), i.e., graphene oxide (GO), reduced graphene oxide (rGO), and poly(ethylene glycol) grafted graphene oxide (GO-PEG), as well as hydroxyapatite (HAp) on the physicochemical and biological properties of the composite hydrogels was examined in view of their potential applicability as tissue engineering scaffolds. The substrates and the hydrogel samples were thoroughly characterized by X-ray photoelectron spectroscopy, X-ray diffractometry, infrared spectroscopy, digital and scanning electron microscopy, rheological and mechanical analysis, in vitro chemical stability and bioactivity assays, as well as initial cytocompatibility evaluation with human umbilical cord Wharton’s jelly mesenchymal stem cells (hUC-MSCs). We followed the green-chemistry approach and avoided toxic cross-linking agents, using instead specific interactions of our polymer matrix with tannic acid, non-toxic physical cross-linker, and graphene derivatives. It was shown that the most promising are the gradient hydrogels modified with GO-PEG and HAp.

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Graphene- and Graphene Oxide-Based Nanocomposite Platforms for Electrochemical Biosensing Applications

International Journal of Molecular Sciences ◽

10.3390/ijms20122975 ◽

2019 ◽

Vol 20 (12) ◽

pp. 2975 ◽

Cited By ~ 25

Author(s):

Madasamy Thangamuthu ◽

Kuan Yu Hsieh ◽

Priyank V. Kumar ◽

Guan-Yu Chen

Keyword(s):

Quantum Dots ◽

Graphene Oxide ◽

High Surface ◽

High Surface Area ◽

Cell Capture ◽

Structure Property ◽

Structure Property Relationships ◽

Electrochemical Biosensing ◽

Graphene Derivatives ◽

Enzymatic Biosensors

Graphene and its derivatives such as graphene oxide (GO) and reduced GO (rGO) offer excellent electrical, mechanical and electrochemical properties. Further, due to the presence of high surface area, and a rich oxygen and defect framework, they are able to form nanocomposites with metal/semiconductor nanoparticles, metal oxides, quantum dots and polymers. Such nanocomposites are becoming increasingly useful as electrochemical biosensing platforms. In this review, we present a brief introduction on the aforementioned graphene derivatives, and discuss their synthetic strategies and structure–property relationships important for biosensing. We then highlight different nanocomposite platforms that have been developed for electrochemical biosensing, introducing enzymatic biosensors, followed by non-enzymatic biosensors and immunosensors. Additionally, we briefly discuss their role in the emerging field of biomedical cell capture. Finally, a brief outlook on these topics is presented.

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Porous Graphene Oxide Decorated Ion Selective Electrode for Observing Across-Cytomembrane Ion Transport

Sensors ◽

10.3390/s20123500 ◽

2020 ◽

Vol 20 (12) ◽

pp. 3500

Author(s):

Shihui Hu ◽

Rong Zhang ◽

Yunfang Jia

Keyword(s):

Graphene Oxide ◽

Ion Transport ◽

Electrochemical Sensors ◽

Ion Selective Electrode ◽

Sodium Iodide Symporter ◽

Selective Electrode ◽

Iodide Uptake ◽

Experimental Conditions ◽

Porous Graphene ◽

Graphene Derivatives

The technology for measuring cytomembrane ion transport is one of the necessities in modern biomedical research due to its significance in the cellular physiology, the requirements for the non-invasive and easy-to-operate devices have driven lots of efforts to explore the potential electrochemical sensors. Herein, we would like to evidence the exploitation of the porous graphene oxide (PGO) decorated ion selective electrode (ISE) as a detector to capture the signal of cytomembrane ion transport. The tumor cells (MDAMB231, A549 and HeLa) treated by iodide uptake operation, with and without the sodium-iodide-symporter (NIS) expression, are used as proofs of concept. It is found that under the same optimized experimental conditions, the changed output voltages of ISEs before and after the cells’ immobilization are in close relation with the NIS related ion’s across-membrane transportation, including I−, Na+ and Cl−. The explanation for the measured results is proposed by clarifying the function of the PGO scaffold interfacial micro-environment (IME), that is, in this spongy-like micro-space, the NIS related minor ionic fluctuations can be accumulated and amplified for ISE to probe. In conclusion, we believe the integration of the microporous graphene derivatives-based IME and ISE may pave a new way for observing the cytomembrane ionic activities.

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Flame retardance of modified graphene to pure cotton fabric

Journal of Fire Sciences ◽

10.1177/0734904117748118 ◽

2017 ◽

Vol 36 (2) ◽

pp. 111-128 ◽

Cited By ~ 3

Author(s):

Hong Liu ◽

Yang Du ◽

Guohai Yang ◽

Guoqing Zhu ◽

Yunji Gao ◽

...

Keyword(s):

Graphene Oxide ◽

Flame Retardant ◽

Cotton Fabric ◽

Combustion Process ◽

Experimental Results ◽

Graphene Oxides ◽

Nitrogen Doped ◽

Nitrogen Doped Graphene ◽

Doped Graphene ◽

Phosphorus Doped

Phosphorus- and nitrogen-doped graphene oxides are conveniently obtained by the modification of as-prepared graphene oxide and characterized by scanning electron microscopy, X-ray powder diffraction, Fourier-transform infrared, and ultraviolet–visible spectra. The combustion performances of pure cotton fabric, respectively, enriched with graphene oxide, phosphorus-doped graphene oxide, and nitrogen-doped graphene oxides, are tested and evaluated. The results show that phosphorus-doped graphene oxide acts as the most promising flame retardant, which can effectively reduce the burning rate and heat release rate of the combustion process, with excellent smoke suppression effect. Based on the relevant parameters obtained from the experimental results of phosphorus-doped graphene oxide, Simtec simulation is operated to demonstrate vertical combustion of thin fabric before and after flame-retardant treatment, and the results are consistent with the trend of the experimental results and suggest a magnifying effect of phosphorus-doped graphene oxide.

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A BRIEF REVIEW ON GRAPHENE-NANOPARTICLE COMPOSITES

COSMOS ◽

10.1142/s0219607710000607 ◽

2010 ◽

Vol 06 (02) ◽

pp. 159-166 ◽

Cited By ~ 10

Author(s):

XIAO HUANG ◽

FREDDY BOEY ◽

HUA ZHANG

Keyword(s):

Graphene Oxide ◽

Surface Defects ◽

Single Layer ◽

Mechanical And Thermal Properties ◽

Photovoltaic Devices ◽

Reduced Graphene ◽

Wide Range ◽

Graphene Derivatives ◽

Enhanced Properties ◽

Nanoparticle Composites

Graphene, a single layer of hexagonal packed carbon atoms, has attracted increasing attention in recent years. Because of its exceptional electronic, optical, mechanical, and thermal properties, graphene has shown great promises in a wide range of applications. Graphene derivatives, e.g. graphene oxide (GO) and reduced graphene oxide (rGO) sheets, possess surface defects and oxygen functional groups, which make them ideal templates for synthesis of metal and semiconductor nanoparticles (NPs). Enhanced properties are expected in these graphene–NP composites, which arise from the synergic effect of the GO/rGO sheets and the anchored NPs. In this review, after a brief introduction on the properties and synthesis of graphene, we will discuss the fabrication methods of graphene–metal NP and graphene–semiconductor NP composites, as well as their related applications in catalysis, photovoltaic devices, supercapacitors, and so on.

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