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Photograph of graphene oxide (left) and bacterially reduced graphene oxide (right) at a concentration of 500 μg/mL.
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This paper describes an environmentally friendly ("green") approach for the synthesis of soluble graphene using Bacillus marisflavi biomass as a reducing and stabilizing agent under mild conditions in aqueous solution. In addition, the study reported here investigated the cytotoxicity effects of graphene oxide (GO) and bacterially reduced graphene...
Contexts in source publication
Context 1
... of GO and B-rGO by UV-vis spectroscopy Figure 1 shows the GO and B-rGO that were produced using the modified method of Hummers and Offeman. 33 To briefly reiterate, the graphite powder was first oxidized into graphite oxide using KMnO 4 /H 2 SO 4 , then the graphite oxide was exfoliated into GO sheets by ultra-sonication in water. ...Context 2
... a typical reduction experiment, 200 mg of bacterial biomass was added to the GO dispersion, and the mixture was stirred at 37°C for 72 hours. GO nanosheets were exfoliated from the graphite oxide, resulting in a clear, homogeneous, yellow-brown GO dispersion (pictured at left in Figure 1) and rGO nanosheets were obtained from the reduction of GO by bacterial biomass (pictured at right in Figure 1). This indicated that bacterial biomass played an important role in the reduction of GO to graphene. ...Context 3
... a typical reduction experiment, 200 mg of bacterial biomass was added to the GO dispersion, and the mixture was stirred at 37°C for 72 hours. GO nanosheets were exfoliated from the graphite oxide, resulting in a clear, homogeneous, yellow-brown GO dispersion (pictured at left in Figure 1) and rGO nanosheets were obtained from the reduction of GO by bacterial biomass (pictured at right in Figure 1). This indicated that bacterial biomass played an important role in the reduction of GO to graphene. ...Context 4
... also indicated by the color change of the solution before and after reaction (from yellow-brown to black), as shown in Figure 1. This can be attributed to the large amount of hydrophilic functional groups, such as carboxyl, hydroxyl, and epoxy groups, on the GO nanosheets. 4 After the visibility check, we examined the water dispersibility of GO and B-rGO using UV-vis spectra analysis. ...Context 5
... investigate the impact of GO and B-rGO on membrane integrity, the cells were treated with various concentrations of GO and B-rGO for 24 hours and then the extracellular LDH activity was measured. The results suggest that cell membrane integrity in MCF-7 cells was compromised by GO and B-rGO at a concentration of 100 µg/mL in a dose-dependent manner ( Figure 10). LDH activity was slightly increased in comparison to the control cells. ...Context 6
... is expressed by the ratio of dead cells in total cells. The cells treated with GO and B-rGO showed significant cell death when compared with untreated cells (Figure 11). Cheng et al 31 observed that biopolymer functionalized rGO exhibits an ultralow hemolysis ratio and good compatibility in human umbilical vein endothelial cells, even at a high concentration of 100 µg/mL. ...Context 7
... the proposed method provides a novel and promising approach for the study of the biological and biomedical applications of graphene. 40 60 B-rGO GO Concentrations (µg/mL) Cell number (10 5 ) 80 100 Figure 11 The effect of graphene oxide (GO) and bacterially reduced graphene oxide (B-rGO) on the mortality of MCF-7 cells. Notes: The mortality of MCF-7 cells was determined using trypan blue assay after 24 hours of exposure to different concentrations of GO or B-rGO. ...Similar publications
Purpose:
Photodynamic therapy (PDT) is gaining increasing recognition for breast cancer treatment because it offers local selectivity and reduced toxic side effects compared to radiotherapy and chemotherapy. In PDT, photosensitizer drugs are loaded in different nanomaterials and used in combination with light exposure. However, the most representa...
Citations
... According to the literature, biologically synthesized GO induces a dose-dependent formation of ROS. The production of ROS is almost doubled in PBMCs after treatment with 250 µg/mL graphene (bio-reduced by crude polysaccharide) for 3 h [36] and significantly higher in MCF-7 cells after treatment with 100 µg/mL bacterially rGO than with an equal dose of chemically produced GO [40]. In our study, ROS production in HaCaT cells was not that high when the cells were treated with bG and cG for longer periods (24 h) but with lower doses (50 µg/mL). ...
... According to the literature, biologically synthesized GO induces a dose-dependent formation of ROS. The production of ROS is almost doubled in PBMCs after treatment with 250 μg/mL graphene (bio-reduced by crude polysaccharide) for 3 h [36] and significantly higher in MCF-7 cells after treatment with 100 μg/mL bacterially rGO than with an equal dose of chemically produced GO [40]. In our study, ROS production in HaCaT cells was not that high when the cells were treated with bG and cG for longer periods (24 h) but with lower doses (50 μg/mL). ...
Graphene has been studied thoroughly for its use in biomedical applications over the last decades. A crucial factor for a material to be used in such applications is its biocompatibility. Various factors affect the biocompatibility and toxicity of graphene structures, including lateral size, number of layers, surface functionalization, and way of production. In this work, we tested that the green production of few-layer bio-graphene (bG) enhances its biocompatibility compared to chemical-graphene (cG). When tested against three different cell lines in terms of MTT assays, both materials proved to be well-tolerated at a wide range of doses. However, high doses of cG induce long-term toxicity and have a tendency for apoptosis. Neither bG nor cG induced ROS generation or cell cycle modifications. Finally, both materials affect the expression of inflammatory proteins such as Nrf2, NF-kB and HO-1 but further research is required for a safe result. In conclusion, although there is little to choose between bG and cG, bG’s sustainable way of production makes it a much more attractive and promising candidate for biomedical applications.
... Graphene oxide reduces the life span of cervical cancer cells, mice fibroblast cells, and breast cancer cells from the MCF-7 and SKBR3 cell lines in which all of the said effects were concentration and time-dependent (48). Another study showed that graphene causes evident cell toxicity in a dosedependent manner which causes the reduction of cell life, increase of ROS, and the release of lactate dehydrogenase in breast cancer cells (49). After being exposed to graphene materials, the activity of SOD and GPx enzymes reduced in a concentration and time-dependent manner. ...
Objectives:
Nanotechnology has helped a lot in diagnosing and treating multiple illnesses, specifically cancer, and increasing the development of targeted drug delivery methods. Nanocomposites are materials with at least one component smaller than 100 nm. Therefore, this study aims to assess the anticancer effects of silver-graphene nanocomposite on MCF-7.
Materials and methods:
In this study, the rate of inhibition of cancer cell growth and production of reactive oxygen radicals, malondialdehyde, and glutathione stores in MCF7 cells were investigated. Cancer cells were exposed to nano particles for 48 hr. Silver nanoparticles and graphene both reduced the growth rate of MCF-7.
Results:
Subsequently, by treating the cells with silver-graphene nanocomposite, the rate of inhibition of cell growth at the highest concentration was 84.60%. Nanoparticles also inhibited the growth of cancer cells through the oxidative stress pathway by increasing the amount of intracellular ROS, followed by increasing malondialdehyde and decreasing glutathione stores, so that at the highest combined concentration of nanoparticles, the amounts of LPO and ROS increased up to 70% and 74 %, and glutathione reserves decreased by 16%.
Conclusion:
Treatment of MCF-7 cells with silver or graphene nanoparticles and combination treatment with these two substances against cisplatin have sound effects, and by affecting oxidative stress factors, such as increased ROS and subsequent increase in lipid membrane damage, inhibit cell growth and proliferation. According to the mathematical model, silver graphene nanocomposite> silver nanoparticles> graphene has the best effect in inhibiting the growth of cancer cells, respectively.
... Cell viability was assessed using the WST-8 test, as previously explained [32,33]. A quantity of 1 × 10 4 cells of A549 was plated in 100 µL of DMEM medium (10% FBS) in a 96-well plate. ...
This study demonstrated the effective reduction of graphene oxide (GO) by employing thiourea as a reducing and stabilizing agent. Two fungi (Aspergillus flavus and Aspergillus fumigatus) were used for anti-fungal assay. Cell viability, cell cycle analysis, DNA fragmentation, and cell morphology were assessed to determine the toxicity of thiourea-reduced graphene oxide (T-rGO) on human lung cancer cells. The results revealed that GO and T-rGO were hazardous to cells in a dose-dependent trend. The viability of both A. fumigatus and A. flavus was affected by GO and T-rGO. The reactive oxygen species produced by T-rGO caused the death of A. flavus and A. fumigatus cells. This study highlighted the effectiveness of T-rGO as an antifungal agent. In addition, T-rGO was found to be more harmful to cancer cells than GO. Thus, T-rGO manifested great potential in biological and biomedical applications.
... GO exerts significant cytotoxicity at a dose > 60 μg/mL. 45 Zhou et al 99 evaluated the toxicity of GO in different cancer cell lines, such as mouse melanoma B16F10, prostate cancer PC3, and breast cancer MDA-MB-231 cells. The results exhibited that GO was cytotoxic to these cancer cells in a dosedependent manner. ...
... Accumulating evidence suggests that GO plays a pivotal role in the treatment of cancers. 45,[135][136][137] Moreover, evidence showing the relationship between GO and endoplasmic reticulum stress and the pathogenesis of ovarian cancer is lacking. To evaluate the effects of GO on the endoplasmic reticulum, SKOV3 cells treated with GO (25 µg/mL), CIS (6 µg/mL), C6-Cer (15 µg/mL), and GW4869 (25 µM) for 24 h. ...
Background:
Exosomes, which are nanovesicles secreted by almost all the cells, mediate intercellular communication and are involved in various physiological and pathological processes. We aimed to investigate the effects of graphene oxide (GO) on the biogenesis and release of exosomes in human ovarian cancer (SKOV3) cells.
Methods:
Exosomes were isolated using ultracentrifugation and ExoQuick and characterized by various analytical techniques. The expression levels of exosome markers were analyzed via quantitative reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay.
Results:
Graphene oxide (10-50 μg/mL), cisplatin (2-10 μg/mL), and C6-ceramide (5-25 μM) inhibited the cell viability, proliferation, and cytotoxicity in a dose-dependent manner. We observed that graphene oxide (GO), cisplatin (CIS), and C6-Ceramide (C6-Cer) stimulated acetylcholine esterase and neutral sphingomyelinase activity, total exosome protein concentration, and exosome counts associated with increased level of apoptosis, oxidative stress and endoplasmic reticulum stress. In contrast, GW4869 treatment inhibits biogenesis and release of exosomes. We observed that the human ovarian cancer cells secreted exosomes with typical cup-shaped morphology and surface protein biomarkers. The expression levels of TSG101, CD9, CD63, and CD81 were significantly higher in GO-treated cells than in control cells. Further, cytokine and chemokine levels were significantly higher in exosomes isolated from GO-treated SKOV3 cells than in those isolated from control cells. SKOV3 cells pre-treated with N-acetylcysteine or GW4869 displayed a significant reduction in GO-induced exosome biogenesis and release. Furthermore, endocytic inhibitors decrease exosome biogenesis and release by impairing endocytic pathways.
Conclusion:
This study identifies GO as a potential tool for targeting the exosome pathway and stimulating exosome biogenesis and release. We believe that the knowledge acquired in this study can be potentially extended to other exosome-dominated pathologies and model systems. Furthermore, these nanoparticles can provide a promising means to enhance exosome production in SKOV3 cells.
... Instead of measuring the thickness of the GO sheet, it examines the Sample's topological surface. As a consequence of the scrolling, typical SEM pictures of GO exhibit 2D nanosheets morphology [124] with wrinkled and folded textures (Fig. 1E) [126][127][128], often uneven edges, rough surfaces, and crumpling [129]. In the same GO sample, SEM analysis revealed GO sheets with lateral dimensions are big as 200 mm and as tiny as a few microns [130]. ...
Recent advancements in nanotechnology have enabled us to develop sophisticated multifunctional nanoparticles or nanosystems for targeted diagnosis and treatment of several illnesses, including cancers. To effectively treat any solid tumor, the therapy should preferably target just the malignant cells/tissue with minor damage to normal cells/tissues. Graphene oxide (GO) nanoparticles have gained considerable interest owing to their two-dimensional planar structure, chemical/mechanical stability, excellent photosensitivity, superb conductivity, high surface area, and good biocompatibility in cancer therapy. Many compounds have been functionalized on the surface of GO to increase their biological applications and minimize cytotoxicity. The review presents an overview of the physicochemical characteristics, strategies for various modifications, toxicity and biocompatibility of graphene and graphene oxide, current trends in developing GO-based nano constructs as a drug delivery cargo and other biological applications, including chemo-photothermal therapy, chemo-photodynamic therapy, bioimaging, and theragnosis in cancer. Further, the review discusses the challenges and opportunities of GO, GO-based nanomaterials for the said applications. Overall, the review focuses on the therapeutic potential of strategically developed GO nanomedicines and comprehensively discusses their opportunities and challenges in cancer therapy.
... Assay. The WST-8 assay was used to determine cell viability, as previously described [52,53]. In a 96-well plate, 1 × 10 4 cells (human prostate cancer PC-3 tumor) were planted in 100 μL Ham's F-12 medium containing 10% FBS. ...
This study was aimed at determining the cytotoxic efficacy of graphene oxide (GO) and thiourea-reduced oxide (T-rGO) nanosheets against human prostate cancer cells and their antibacterial activity against E. coli mastitis. X-ray diffraction, Raman spectroscopy, Fourier transformed infrared spectroscopy, and scanning electron microscopy were used to study the physicochemical properties of the fabricated GO and T-rGO. The cytotoxicity of GO and T-rGO in human prostate cancer cells was examined using cell survival test, DNA laddering, and cell cycle analysis. The antibacterial effectiveness of GO and T-rGO was tested using E. coli mastitis. The study revealed that cell viability was lowered by GO and T-rGO in a concentration-dependent trend. The production of reactive oxygen species and hydroxyl radicals was found to increase following the treatment. DNA was harmed because of oxidative stress, causing laddering. Both GO and T-rGO demonstrated good antibacterial activity against E. coli mastitis. The findings of this research work provide insightful information about functional graphene derivatives for potential biomedical applications, primarily cancer treatment.
... Graphene or GO sheets were tested for toxicity against various cell types, including cancer cells. In cancer cells of the human breast [33] and cancer cells of the ovary [34], our research team found that physiologically, a lower amount of graphene causes more toxicity. Zhang et al. [35] used a combination of photothermal and chemotherapy agents to demonstrate the anticancer impact of NGO-PEG-DOX (nanoscale graphene oxide-polyethylene glycol-doxorubicin). ...
... The WST-8 test was used to determine cell viability, as previously described [33,47]. In a 96-well plate, 1 × 10 4 cells were planted in 100 µL of 10% FBS-containing MEM. ...
The current research focuses on the fabrication of water-soluble, reduced graphene oxide (rGO) employing thiourea (T) using a simple cost-effective method, and subsequently examining its anticancer characteristics. The cytotoxicity caused by graphene oxide (GO) and T-rGO is investigated in detail. Biological results reveal a concentration-dependent toxicity of GO and T-rGO in human colon cancer cells HT-29. A decrease in cell viability alongside DNA fragmentation is observed. Flow cytometry analysis confirms the cytotoxic effects. The novelty in this work is the use of raw graphite powder, and oxidants such as KMNO4, NaNO3, and 98 percent H2SO4 to produce graphene oxide by a modified Hummers method. This study demonstrates a simple and affordable procedure for utilising thiourea to fabricate a water-soluble reduced graphene oxide, which will be useful in a variety of biomedical applications.
... The generation of ROS by nanoparticles benefits antibacterial function on the one hand, while on the other hand it may promote cytotoxicity risks [83][84][85]. Moderate oxidative stress can activate antioxidant reactions, which results in the recovery of redox homeostasis [84]. However, cellular apoptosis and necrosis may happen as a result of the collapse of the defense system under a high concentration of ROS [86]. ...
... The generation of ROS by nanoparticles benefits antibacterial function on the one hand, while on the other hand it may promote cytotoxicity risks [83][84][85]. Moderate oxidative stress can activate antioxidant reactions, which results in the recovery of redox homeostasis [84]. However, cellular apoptosis and necrosis may happen as a result of the collapse of the defense system under a high concentration of ROS [86]. ...
... Some of them suggest that rGO has excellent biocompatibility [87] and promotes the proliferation of L929, MG63 [88,89], and HFOB cells [90,91]. Others have reported some cytotoxic effects of rGO on MC3T3-E1 [92], MCF-7 [84], and A549 [85] and size-dependent toxicity on hMSCs cells [93]. Various factors, including ROS generation, high rGO concentration, large rGO size, and long exposure times have been reported to be detrimental to cell viability [94]. ...
Nanoparticles (NPs) have high multifunctional potential to simultaneously enhance implant osseointegration and prevent infections caused by antibiotic-resistant bacteria. Here, we present the first report on using plasma electrolytic oxidation (PEO) to incorporate different combinations of reduced graphene oxide (rGO) and silver (Ag) NPs on additively manufactured geometrically ordered volume-porous titanium implants. The rGO nanosheets were mainly embedded parallel with the PEO surfaces. However, the formation of ‘nano-knife’ structures (particles embedded perpendicularly to the implant surfaces) was also found around the pores of the PEO layers. Enhanced in vitro antibacterial activity against methicillin-resistant Staphylococcus aureus was observed for the rGO+Ag-containing surfaces compared to the PEO surfaces prepared only with AgNPs. This was caused by a significant improvement in the generation of reactive oxygen species, higher levels of Ag+ release, and the presence of rGO ‘nano-knife’ structures. In addition, the implants developed in this study stimulated the metabolic activity and osteogenic differentiation of MC3T3-E1 preosteoblast cells compared to the PEO surfaces without nanoparticles. Therefore, the PEO titanium surfaces incorporating controlled levels of rGO+Ag nanoparticles have high clinical potential as multifunctional surfaces for 3D-printed orthopaedic implants.
... In several studies performed on breast cancer cells (i.e., MCF-7, MDA-MB-231 and 4T1 cells) [119,135,147,148], naked and functionalized GO have demonstrated the ability to induce cell death in such pathological cells by inducing the generation of ROS species. Farell et al. showed different trends of oxidative stress in two cancerous (i.e., MCF-7 and MDA-MB-231) and one non-cancerous (i.e., MCF-10A) cell line ( Figure 5) [119] when exposed to naked and lipid-functionalized rGO carriers. ...
... (A) Generation of ROS in MCF-7 cells induced by GO and bacteria-reduced GO (B-rGO) (treated groups showed statistically significant higher ROS production with respect to the control (*: p < 0.05)). The figure is adapted from[147], copyright 2013 Gurunathan et al., originally published by and used with permission from Dove Medical Press Ltd. (B) ROS production induced by rGO in MDA-MB-231 and ZR-75-1 cells with different concentrations of nanoparticles. The figure is adapted with open-access permission from [118], copyright 2021 Kretowski et al., publisher and licensee MDPI. ...
Functionalized graphene oxide (GO) nanoparticles are being increasingly employed for designing modern drug delivery systems because of their high degree of functionalization, high surface area with exceptional loading capacity, and tunable dimensions. With intelligent controlled release and gene silencing capability, GO is an effective nanocarrier that permits the targeted delivery of small drug molecules, antibodies, nucleic acids, and peptides to the liquid or solid tumor sites. However, the toxicity and biocompatibility of GO-based formulations should be evaluated, as these nanomaterials may introduce aggregations or may accumulate in normal tissues while targeting tumors or malignant cells. These side effects may potentially be impacted by the dosage, exposure time, flake size, shape, functional groups, and surface charges. In this review, the strategies to deliver the nucleic acid via the functionalization of GO flakes are summarized to describe the specific targeting of liquid and solid breast tumors. In addition, we describe the current approaches aimed at optimizing the controlled release towards a reduction in GO accumulation in non-specific tissues in terms of the cytotoxicity while maximizing the drug efficacy. Finally, the challenges and future research perspectives are briefly discussed.
... While graphene nanomaterials have the ability to damage cell viability by inducing oxidative stress and damaging cell membranes, they can also directly induce apoptosis or necrosis by altering the normal functions of cell mitochondria [201,202]. Accordingly, graphene nanomaterials are capable of increasing oxygen consumption levels of mitochondria and activating mitochondrial pathways that eventually trigger apoptosis [203]. For example, GO has been reported to increase the electron supply to specific mitochondrial complexes and thus promote the generation of ROS in MHC cells [204]. ...
With the glorious discovery of graphene back in 2004, the field of nanotechnology was faced with a breakthrough that soon attracted the attention of many scientists from all over the world. Owing to its unique bidimensional structure and exquisite physicochemical properties, graphene has successfully managed to cave its way up to the list of the most investigated topics, while being extensively used in various fields of science and technology. However, serious concerns have been raised about the safety of graphene, for which numerous studies have been conducted to evaluate the toxicity of graphene derivatives in both in vitro and in vivo conditions. The reproductive toxicity of graphene is one of the most important aspects of this subject as it not only affects the individual but can also potentially put the health of one’s offsprings at risk and display long-term toxic effects. Given the crucial importance of graphene’s reproductive toxicity, more attention has been recently shifted toward this subject; however, the existing literature remains insufficient. Therefore, we have conducted this review with the aim of providing researchers with assorted information regarding the toxicity of graphene derivatives and their underlying mechanisms, while mentioning some of the major challenges and gaps in the current knowledge to further elucidate the path to exploring graphene’s true nature. We hope that our work will effectively give insight to researchers who are interested in this topic and also aid them in completing the yet unfinished puzzle of graphene toxicity.
