Graphene Family of Nanomaterials: Reviewing Advanced Applications in Drug delivery and Medicine

Assessment of the Effects of Albendazole-Loaded Sulfonated Graphene Oxide on Echinococcus granulosus Protoscoleces: An In Vitro Investigation

Objectives

Due to Albendazole's relatively low efficacy and bioavailability, Echinococcosis has proven a challenge to manage successfully, with several studies investigating ways to improve the outcome, mainly showing mixed results. We, therefore, aimed to evaluate whether Sulfonated Graphene Oxide (S-GO), as nanocarriers, could improve the mentioned outcome.

Methods

Echinococcus protoscoleces were divided into four groups based on the agent they received, which comprised control, S-GO, Albendazole, and Albendazole-loaded S-GO (S-GO-Albendazole). Then, the Bax and Bcl-2 gene expression levels and the number of surviving protoscoleces in each group were determined.

Results

Bax gene expression increased by 121% in the 50 μg/ml concentration of the S-GO-Albendazole, while Bcl-2 gene expression decreased by 64%. Moreover, S-GO-Albendazole was approximately 18% more effective at neutralizing protoscoleces than Albendazole and 14% and 31% more effective at improving the expression of the mentioned genes, respectively (p < 0.05). In addition, the number of surviving protoscoleces after exposure to the mentioned concentration reduced by approximately 99%.

Conclusions

S-GO, despite not having significant lethality on protoscoleces, significantly increased the lethality of Albendazole and, therefore, is a suitable nanocarrier. However, we recommend conducting in vivo and clinical studies to more accurately determine this nanocomplex's potential and side effects.

The Potentiating Effect of Graphene Oxide on the Arylhydrocarbon Receptor (AhR)-Cytochrome P4501A (Cyp1A) System Activated by Benzo(k)fluoranthene (BkF) in Rainbow Trout Cell Line

The increasing use of graphene oxide (GO) will result in its release into the environment; therefore, it is essential to determine its final fate and possible metabolism by organisms. The objective of this study was to assess the possible role of the aryl hydrocarbon receptor (AhR)-dependent cytochrome P4501A (Cyp1A) detoxification activities on the catabolism of GO. Our hypothesis is that GO cannot initially interact with the AhR, but that after an initial degradation caused by other mechanisms, small fractions of GO could activate the AhR, inducing Cyp1A. The environmental pollutant benzo(k)fluoranthene (BkF) was used for the initial activation of the AhR in the rainbow trout (Oncorhynchus mykiss) cell line RTL-W1. Pre-, co-, and post-exposure experiments with GO were performed and Cyp1A induction was monitored. The strong stimulation of Cyp1A observed in cells after exposure to GO, when BkF levels were not detected in the system, suggests a direct action of GO. The role of the AhR was confirmed by a blockage of the observed effects in co-treatment experiments with αNF (an AhR antagonist). These results suggest a possible role for the AhR and Cyp1A system in the cellular metabolism of GO and that GO could modulate the toxicity of environmental pollutants.

The antimicrobial efficacy of nanographene oxide and double antibiotic paste per se and in combination: part II

BACKGROUND

Finding strategies to overcome the rising trends of antimicrobial resistance against currently available antimicrobial agents has become increasingly relevant. Graphene oxide has recently emerged as a promising material due to its outstanding physicochemical and biological properties. This study aimed to validate previous data on the antibacterial activity of nanographene oxide (nGO), double antibiotic paste (DAP), and their combination (nGO-DAP).

METHODS

The antibacterial evaluation was performed against a wide range of microbial pathogens. Synthesis of nGO was achieved using a modified Hummers' method, and loading it with ciprofloxacin and metronidazole resulted in nGO-DAP. The microdilution method was utilized to assess the antimicrobial efficacy of nGO, DAP, and nGO-DAP against two gram-positive bacteria (S. aureus and E. faecalis), two gram-negative bacteria (E. coli, and S. typhi), and an opportunistic pathogenic yeast (C. albicans). Statistical analysis was conducted using one-sample t-test and one-way ANOVA (α = 0.05).

RESULTS

All three antimicrobial agents significantly increased the killing percent of microbial pathogens compared to the control group (P < 0.05). Furthermore, the synthesized nGO-DAP exhibited higher antimicrobial activity than nGO and DAP per se.

CONCLUSION

The novel synthesized nGO-DAP can be used as an effective antimicrobial nanomaterial for use in dental, biomedical, and pharmaceutical fields against a range of microbial pathogens, including gram-negative and gram-positive bacteria, as well as yeasts.

Potential Biomedical Limitations of Graphene Nanomaterials

Graphene-family nanomaterials (GFNs) possess mechanical stiffness, optical properties, and biocompatibility making them promising materials for biomedical applications. However, to realize the potential of graphene in biomedicine, it must overcome several challenges that arise when it enters the body's circulatory system. Current research focuses on the development of tumor-targeting devices using graphene, but GFNs accumulated in different tissues and cells through different pathways, which can cause toxic reactions leading to cell apoptosis and body dysfunction when the accumulated amount exceeds a certain limit. In addition, as a foreign substance, graphene can induce complex inflammatory reactions with immune cells and inflammatory factors, potentially enhancing or impairing the body's immune function. This review discusses the biomedical applications of graphene, the effects of graphene materials on human immune function, and the biotoxicity of graphene materials.

Interactions of airborne graphene oxides with the sexual reproduction of a model plant: When production impurities matter

The increasing use of graphene-related materials (GRMs) in everyday-life products raises concerns for their possible release into the environment and consequent impact on organisms. GRMs have widely varying effects on plants and, according to recent evidences, graphene oxide (GO) has the potential to interfere with the sexual reproduction owing to its acidic properties and production residues. Here, stigmas of the model plant Cucurbita pepo (summer squash) were subjected to simulated dry depositions of GO and GO purified from production residues (PGO). Stigmas were then hand-pollinated and GRM deposition was checked by ESEM and confocal microscopy. Analysis of stigma integrity, pH homeostasis and pollen-stigma interactions did not reveal negative effects. Fruit and seed production were not affected, but GO depositions of 22.1 ± 7.2 ng mm^-2 affected the normal development of seeds, decreasing seed dimensions, seed germination and germination speed. The elemental analysis revealed that GO has significant quantities of production residues, such as strong acids and oxidants, while PGO has only traces, which justifies the differences observed in the effects caused by the two materials. Our results show that GO depositions of up to 11.1 ± 3.6 ng mm^-2, which fall within the variation range of total dry particulate matter depositions reported in the literature, are safe for reproduction of C. pepo. This is the first "safety" limit ever recorded for depositions of "out-of-the-box" GO concerning the reproduction of a seed plant. If confirmed for wind-pollinated species, it might be considered for policymaking of GRMs emissions in the air.

Antimicrobial Activity of Graphene-Based Nanocomposites: Synthesis, Characterization, and Their Applications for Human Welfare

Graphene (GN)-related nanomaterials such as graphene oxide, reduced graphene oxide, quantum dots, etc., and their composites have attracted significant interest owing to their efficient antimicrobial properties and thus newer GN-based composites are being readily developed, characterized, and explored for clinical applications by scientists worldwide. The GN offers excellent surface properties, i.e., a large surface area, pH sensitivity, and significant biocompatibility with the biological system. In recent years, GN has found applications in tissue engineering owing to its impressive stiffness, mechanical strength, electrical conductivity, and the ability to innovate in two-dimensional (2D) and three-dimensional (3D) design. It also offers a photothermic effect that potentiates the targeted killing of cells via physicochemical interactions. It is generally synthesized by physical and chemical methods and is characterized by modern and sophisticated analytical techniques such as NMR, Raman spectroscopy, electron microscopy, etc. A lot of reports show the successful conjugation of GN with existing repurposed drugs, which improves their therapeutic efficacy against many microbial infections and also its potential application in drug delivery. Thus, in this review, the antimicrobial potentialities of GN-based nanomaterials, their synthesis, and their toxicities in biological systems are discussed.

Possible Synergies of Nanomaterial-Assisted Tissue Regeneration in Plasma Medicine: Mechanisms and Safety Concerns

Cold atmospheric plasma and nanomedicine originally emerged as individual domains, but are increasingly applied in combination with each other. Most research is performed in the context of cancer treatment, with only little focus yet on the possible synergies. Many questions remain on the potential of this promising hybrid technology, particularly regarding regenerative medicine and tissue engineering. In this perspective article, we therefore start from the fundamental mechanisms in the individual technologies, in order to envision possible synergies for wound healing and tissue recovery, as well as research strategies to discover and optimize them. Among these strategies, we demonstrate how cold plasmas and nanomaterials can enhance each other's strengths and overcome each other's limitations. The parallels with cancer research, biotechnology and plasma surface modification further serve as inspiration for the envisioned synergies in tissue regeneration. The discovery and optimization of synergies may also be realized based on a profound understanding of the underlying redox- and field-related biological processes. Finally, we emphasize the toxicity concerns in plasma and nanomedicine, which may be partly remediated by their combination, but also partly amplified. A widespread use of standardized protocols and materials is therefore strongly recommended, to ensure both a fast and safe clinical implementation.

Is airborne graphene oxide a possible hazard for the sexual reproduction of wind-pollinated plants?

Products containing graphene-related materials (GRMs) are becoming increasingly common, allowing GRM nanoparticles (NPs) to enter the environment during their life cycle. Thanks to their lightness and bidimensional geometry, GRM NPs can be easily dispersed in the air and travel very long distances. The flowers of wind-pollinated plants may be exposed to airborne GRMs, being apt to intercept pollen from the air and, inevitably, other airborne particles. Here, stigmas of four wind-pollinated plants (Corylus avellana, common hazel; Juglans regia, walnut; Quercus ilex, holm oak; Zea mays, maize) were exposed to airborne graphene oxide (GO) and GO purified from production residues (PGO) at a concentration of 3.7 ng m^-3. Subsequently, the stigmas were pollinated and the adhesion of GOs and their effects on stigma integrity and pollen-stigma interaction were examined. The effect of GO NPs in presence of liquid water on the stigma of C. avellana was also investigated. GOs NPs were intercepted by all species, but their effect varied among them. GO reduced pollen adhesion in J. regia and Q. ilex, whereas pollen germination was unaffected in all four species. The presence of a film of water neither completely removed GO NPs from the stigma, nor it enhanced the toxic effect of GO acidity. PGO never affected pollen-stigma interaction, indicating that the phytotoxic substances used for the production of GO, still in traces in commercial GO, are the main cause of GO toxicity. These results reconfirm the need to verify GRMs effects also on key biological processes beside single model organisms.

CRISPR/Cas9 in cancer therapy: A review with a special focus on tumor angiogenesis

Tumor angiogenesis is a critical target for cancer treatment and its inhibition has become a common anticancer approach following chemotherapy. However, due to the simultaneous activation of different compensatory molecular mechanisms that enhance tumor angiogenesis, clinically authorized anti-angiogenic medicines are ineffective. Additionally, medications used to treat cancer have an effect on normal body cells; nonetheless, more research is needed to create new cancer therapeutic techniques. With advances in molecular biology, it is now possible to use gene-editing technology to alter the genome and study the functional changes resulting from genetic manipulation. With the development of CRISPR/Cas9 technology, it has become a very powerful tool for altering the genomes of many organisms. It was determined that CRISPR/Cas9, which first appeared in bacteria as a part of an adaptive immune system, could be used, in modified forms, to alter genomes and function. In conclusion, CRISPR/Cas9 could be a major step forward to cancer management by providing patients with an effective method for dealing with cancers by dissecting the carcinogenesis pathways, identifying new biologic targets, and perhaps arming cancer cells with drugs. Hence, this review will discuss the current applications of CRISPR/Cas9 technology in tumor angiogenesis research for the purpose of cancer treatment.

Recent advances in Shrimp aquaculture wastewater management

Aquaculture has been celebrated globally and believed to usher in a viable alternative to capture fisheries. It is most welcomed especially now that the world population explosion has pushed the demand on fisheries products to worrisome limits. Shrimp farming is an area of aquaculture that has witnessed significant growth in recent years, contributing substantially to the global aquaculture production. However, intensification of shrimp aquaculture has come with unintended consequences such as wastewater management and other problems emanating from environmental impact of the wastewater. This study identified excess feed and fertilizer application, metabolite wastes, shrimp mortalities, oil spillage from farm machines, drug and chemical abuse as some of the activities contributing to wastewater generation in shrimp aquaculture farming. The impact of shrimp effluent water discharged has been observed to be socio-economic with both positive and negative dimensions. In attempt to overcome the overwhelming problems associated with shrimp effluent water and bring reassurances to its sustainability, a good number of new technological approaches have been identified including caviation, high-rate algal pond system, use of nanomaterials, biofloc technology, nanoadsorbent and polymeric nanoadsorbents. Although all have been proven to be useful, none could boast of a complete and integrated approach that considers all the technological, legal, social, environmental, public health and institutional concerns.

Recent advances in graphene nanoribbons for biosensing and biomedicine

In recent years, a new type of quasi-one-dimensional graphene-based material, graphene nanoribbons (GNRs), has attracted increasing attention. The limited domain width and rich edge configurations of GNRs endow them with unique properties and wide applications in comparison to two-dimensional graphene. This review article mainly focuses on the electrical, chemical and other properties of GNRs, and further introduces the typical preparation methods of GNRs, including top-down and bottom-up strategies. Then, their biosensing and biomedical applications are highlighted in detail, such as biosensors, photothermal therapy, drug delivery, etc. Finally, the challenges and future prospects in the synthesis and application of functionalized GNRs are discussed. It is expected that GNRs will have significant practical use in biomedical applications in the future.

Potential of carbohydrate-conjugated graphene assemblies in biomedical applications

Graphene displays various properties like optical, electrical, mechanical, etc. resulting in a large range of applications in biosensing, bio-imaging, medical and electronic devices. The graphene-based nanomaterials show disadvantages like hydrophobic surface, degradation of biomolecules (proteins and amino acids) and toxicity to the human and microbes by permeating into the cells and thus, limiting the use in the biomedical field. Conjugation of carbohydrates like chitin, cyclodextrins and cellulose with graphene results in thermal stability, oxygen repulsive ability, fire-retardant and gelling properties with better biodegradability, biocompatibility and safety leading to the formation of environment-friendly biopolymers. This article delivers an overview of the molecular interaction of different carbohydrates-derived from natural sources like marine, plants and microbes with graphene nanosheets to extend the applications in tissue engineering, surgical materials, biosensing and novel drug delivery for prolonged action in the treatment of breast and hepatic cancers.

Effects of Few-Layer Graphene on the Sexual Reproduction of Seed Plants: An In Vivo Study with Cucurbita pepo L

Products containing graphene-related materials (GRMs) are becoming quite common, raising concerns for environmental safety. GRMs have varying effects on plants, but their impact on the sexual reproduction process is largely unknown. In this study, the effects of few-layer graphene (FLG) and a similarly layered phyllosilicate, muscovite mica (MICA), were tested in vivo on the reproductive structures, i.e., pollen and stigma, of Cucurbita pepo L. ssp. pepo 'greyzini' (summer squash, zucchini). Pollen was exposed to FLG or MICA, after careful physical-chemical characterization, at concentrations of 0.5 and 2 mg of nanomaterial (NM) per g of pollen for up to six hours. Following this, pollen viability was tested. Stigmas were exposed to FLG or MICA for three hours and then analyzed by environmental scanning electron microscopy to verify possible alterations to their surface. Stigmas were then hand-pollinated to verify the effects of the two NMs on pollen adhesion and in vivo pollen germination. FLG and MICA altered neither pollen viability nor the stigmatic surface. However, both NMs equivalently decreased pollen adhesion and in vivo germination compared with untreated stigmas. These effects deserve further attention as they could impact on production of fruits and seeds. Importantly, it was shown that FLG is as safe as a naturally occurring nanomaterial.

CRISPR-Cas systems: Overview, innovations and applications in human disease research and gene therapy

Genome editing is the modification of genomic DNA at a specific target site in a wide variety of cell types and organisms, including insertion, deletion and replacement of DNA, resulting in inactivation of target genes, acquisition of novel genetic traits and correction of pathogenic gene mutations. Due to the advantages of simple design, low cost, high efficiency, good repeatability and short-cycle, CRISPR-Cas systems have become the most widely used genome editing technology in molecular biology laboratories all around the world. In this review, an overview of the CRISPR-Cas systems will be introduced, including the innovations, the applications in human disease research and gene therapy, as well as the challenges and opportunities that will be faced in the practical application of CRISPR-Cas systems.

Poly(lactic-co-glycolic acid) nanomaterial-based treatment options for pain management: a review

Neuropathic pain is one of the most intense types of chronic pain; it constitutes a pervasive complaint throughout the public health system. With few effective treatments, it remains a significant challenge. Commercially available drugs for neuropathic pain are still limited and have disappointing efficacy. Therefore, chronic neuropathic pain imposes a tremendous burden on patients' quality of life. Recently, the introduction and application of nanotechnology in multiple fields has accelerated the development of new drugs. This review highlights the application of poly(lactic-co-glycolic acid) nanomaterial-based vehicles for drug delivery and how they improve the therapeutic outcomes for neuropathic pain treatment. Finally, future developments for pain research and effective management are presented.

Carbon-based antiviral nanomaterials: graphene, C-dots, and fullerenes. A perspective

The appearance of new and lethal viruses and their potential threat urgently requires innovative antiviral systems. In addition to the most common and proven pharmacological methods, nanomaterials can represent alternative resources to fight viruses at different stages of infection, by selective action or in a broad spectrum. A fundamental requirement is non-toxicity. However, biocompatible nanomaterials have very often little or no antiviral activity, preventing their practical use. Carbon-based nanomaterials have displayed encouraging results and can present the required mix of biocompatibility and antiviral properties. In the present review, the main candidates for future carbon nanometric antiviral systems, namely graphene, carbon dots and fullerenes, have been critically analysed. In general, different carbon nanostructures allow several strategies to be applied. Some of the materials have peculiar antiviral properties, such as singlet oxygen emission, or the capacity to interfere with virus enzymes. In other cases, nanomaterials have been used as a platform for functional molecules able to capture and inhibit viral activity. The use of carbon-based biocompatible nanomaterials as antivirals is still an almost unexplored field, while the published results show promising prospects.

Carbonaceous Nanomaterials Employed in the Development of Electrochemical Sensors Based on Screen-Printing Technique—A Review

This paper aims to revise research on carbonaceous nanomaterials used in developing sensors. In general, nanomaterials are known to be useful in developing high-performance sensors due to their unique physical and chemical properties. Thus, descriptions were made for various structural features, properties, and manner of functionalization of carbon-based nanomaterials used in electrochemical sensors. Of the commonly used technologies in manufacturing electrochemical sensors, the screen-printing technique was described, highlighting the advantages of this type of device. In addition, an analysis was performed in point of the various applications of carbon-based nanomaterial sensors to detect analytes of interest in different sample types.

Function of c-type cytochromes of Shewanella xiamenensis in enhanced anaerobic bioreduction of Cr(VI) by graphene oxide and graphene oxide/polyvinyl alcohol films

Graphene-based materials have been demonstrated to facilitate electron extracellular transfer (EET) of Shewanella. In this study, compared to group lacking graphene oxide (GO)-based materials, GO films-added group and graphene oxide/polyvinyl alcohol (GO/PVA) film-added group delivered 2.67- and 3.13-fold increases in the Cr(VI) reduction by Shewanella xiamenensis, respectively. The whole reduction process could be divided into three stages, including microbial Cr(VI) reduction and GO reduction stage, microbial GO reduction stage and microbial Cr(VI) reduction mediated by reduced graphene oxide (rGO) stage. Moreover, gene analysis revealed that addition of GO and GO/PVA films stimulated overexpression of several c-type cytochrome (c-Cyts) genes, including mtrA, mtrB, mtrC, mtrD, mtrE, mtrF, omcA, petC and SO-4047. Specifically, appreciable Cr(VI) reduction by the strains that overexpressed mtrA, mtrB, mtrC, mtrD, mtrE, mtrF and omcA further confirmed that overexpression of c-Cyts genes indeed enhanced the efficiency of Cr(VI) reduction. Based on these results, the specific function of every c-Cyt was clearly found in Cr(VI) reduction by the induction of GO-based materials. Our finding has disclosed a synergetic mechanism stimulated by GO-based materials to enhance Cr(VI) bioreduction that was not only mediated through the modification of material but also upregulated the expression of functional genes.

Interactions of graphene oxide and graphene nanoplatelets with the in vitro Caco-2/HT29 model of intestinal barrier

Carbon-based nanomaterials are being increasingly used, demanding strong information to support their safety in terms of human health. As ingestion is one of the most important exposure routes in humans, we have determined their potential risk by using an in vitro model simulating the human intestinal barrier and evaluated the effects of both graphene oxide (GO) and graphene nanoplatelets (GNPs). A coculture of differentiated Caco-2/HT29 cells presenting inherent intestinal epithelium characteristics (i.e. mucus secretion, brush border, tight junctions, etc.) were treated with GO or GNPs for 24 h. Different endpoints such as viability, membrane integrity, NPs localization, cytokines secretion, and genotoxic damage were evaluated to have a wide view of their potentially harmful effects. No cytotoxic effects were observed in the cells that constitute the barrier model. In the same way, no adverse effects were detected neither in the integrity of the barrier (TEER) nor in its permeability (LY). Nevertheless, a different bio-adhesion and biodistribution behavior was observed for GO and GNPs by confocal microscopy analysis, with a more relevant uptake of GNPs. No oxidative damage induction was detected, either by the DCFH-DA assay or the FPG enzyme in the comet assay. Conversely, both GO and GNPs were able to induce DNA breaks, as observed in the comet assay. Finally, low levels of anti-inflammatory cytokines were detected, suggesting a weak anti-inflammatory response. Our results show the moderate/severe risk posed by GO/GNPs exposures, given the observed genotoxic effects, suggesting that more extensive genotoxic evaluations must be done to properly assess the genotoxic hazard of these nanomaterials.