Chemical Barriers Research Articles

Chimeric Antigen Receptor (CAR) T-Cell Therapy for Patients with Lung Cancer: Current Perspectives.

Immunotherapy using chimeric antigen receptor (CAR)-engineered T-cells has achieved unprecedented efficacy in selected hematological cancers. However, solid tumors such as lung cancer impose several additional challenges to the attainment of clinical success using this emerging therapeutic modality. Lung cancer is the biggest cause of cancer-related mortality worldwide, accounting for approximately 1.8 million deaths worldwide each year. Obstacles to the development of CAR T-cell immunotherapy for lung cancer include the selection of safe tumor-selective targets, accounting for the large number of candidates that have been evaluated thus far. Tumor heterogeneity is also a key hurdle, meaning that single target-based approaches are susceptible to therapeutic failure through the emergence of antigen null cancers. There is also a need to enable CAR T-cells to traffic efficiently to sites of disease, to infiltrate tumor deposits and to operate within the hostile tumor microenvironment formed by solid tumors, resisting the onset of exhaustion. Multiple immune, metabolic, physical and chemical barriers operate at the core of malignant lesions, with potential for further heterogeneity and evolution in the face of selective therapeutic pressures. Although the extraordinarily adaptable nature of lung cancers has recently been unmasked, immunotherapy using immune checkpoint blockade can achieve long-term disease control in a small number of patients, establishing clinical proof of concept that immunotherapies can control advanced lung carcinomas. This review summarizes pre-clinical CAR T-cell research that is specifically focused on lung cancer in addition to published and ongoing clinical trial activity. A number of advanced engineering strategies are also described which are designed to bridge the gap to the attainment of meaningful efficacy using genetically engineered T-cells.

Microwave irradiation for the recovery enhancement of fly ash components: Thermodynamic and kinetic aspects

This study investigated the use of microwave-assisted leaching to recover the vanadium (V) and nickel (Ni) of fly ash collected from power plants. The fly ash sample was characterized using XRF, ICP-OES, powder X-ray diffraction, FESEM, and a laser particle size analyzer. The sample was found to be valuable as well as hazardous due to the presence of a considerable amount of base and heavy metals with an 80% passing particle size of 70 micrometers. Conventional leaching tests were performed using sulfuric acid (H2SO4), which resulted in 91.2% V, 80.5% Ni, and 57.6% Fe recoveries. Full recovery of the aforementioned components was achieved by adding 10% v/v hydrogen peroxide (H2O2). Microwave-assisted leaching showed promise, with comparable recoveries for Ni and V (complete recovery) at a microwave power of 700 W and a retention time of 30 mins, without the addition of any chemical additive. The study provided thermodynamic and kinetic justification for the efficient dissolution of V and Ni, which occurs via rapid boiling of the sulfuric acid solution (19.5% v/v) overcoming the chemical and liquid diffusion kinetic barriers. This work concludes that microwave-assisted leaching is an effective method for recovering heavy metals from fly ash samples as a complex solid waste.

Study on anaerobic fermentation of waste activated sludge to produce volatile fatty acids by thermal–rhamnolipid treatment

AbstractBACKGROUNDThe extracellular polymer and cell wall of waste activated sludge serve as chemical barriers for anaerobic fermentation, limiting the recycling and utilization of organic carbon contained in the sludge. To improve the efficiency of anaerobic fermentation, this paper proposes thermal–rhamnolipid (T‐RL) pretreatment technology and systematically discusses the effect of T‐RL treatment on the anaerobic fermentation of waste activated sludge for acid production from the perspective of organic matter dissolution characteristics, total volatile fatty acid (VFA) content, composition and microbial changes.RESULTST‐RL treatment significantly promoted the dissolution of organic matter in sludge, with soluble chemical oxygen demand solubilizing to 6097.78–7375.56 mg L−1, soluble carbohydrates solubilizing to 207.38–274.74 mg L−1, and the dissolution of soluble proteins and DNA also at a high level. Both treatment factors significantly promoted the enrichment of acid‐producing microorganisms, especially acetic acid‐producing microorganisms. The best VFA production conditions of T‐RL treatment were 60 mg g−1 total solids and 70 °C, and the yield was 3294.96 mg L−1. Compared with thermal and RL treatments, the optimum yield of T‐RL treatment increased by 33.16% and 22.06%, respectively. The VFA components in the T‐RL group were mainly acetic acid and propionic acid. Under optimal conditions, the proportion of acetic acid and propionic acid reached 77%.CONCLUSIONT‐RL treatment can promote sludge disintegration and organic matter conversion through the coupling effect of thermal and RL treatments, providing sufficient and high‐quality substrate for acid‐producing microorganisms, effectively enriching VFA producers, and thus improving the efficiency of anaerobic fermentation for VFA production. This treatment technology will provide some beneficial references for the future utilization of sludge resources. © 2023 Society of Chemical Industry (SCI).

WS09.03 Delivery characterisation of SPL84 Inhaled Antisense Oligonucleotide

The last years shown enormous advancement in the therapeutic potential of RNA treatments, specifically antisense oligonucleotides (ASO), leading to increased numbers of ASO regulatory approvals. SpliSense is developing inhaled ASOs for the treatment of pulmonary diseases; among them are Cystic Fibrosis (CF) mutations with an unmet need. SpliSense’s most advanced program, SPL84, modulates the splicing to produce normal CFTR proteins in 3849 + 10 kb C->T patients. SPL84 was shown to restore CFTR activity in patient cells. Pulmonary drug delivery is challenging, due to a variety of biological, physical, chemical, and structural barriers, especially when targeting the nucleus where splicing occurs. The thick mucus layer covering CF airways is a greater obstacle for drug penetration.

Plasmon-Enhanced Photocatalytic CO2 Reduction for Higher-Order Hydrocarbon Generation Using Plasmonic Nano-Finger Arrays.

The carbon dioxide reduction reaction (CO2RR) is a promising method to both reduce greenhouse gas carbon dioxide (CO2) concentrations and provide an alternative to fossil fuel by converting water and CO2 into high-energy-density chemicals. Nevertheless, the CO2RR suffers from high chemical reaction barriers and low selectivity. Here we demonstrate that 4 nm gap plasmonic nano-finger arrays provide a reliable and repeatable plasmon-resonant photocatalyst for multiple-electrons reactions: the CO2RR to generate higher-order hydrocarbons. Electromagnetics simulation shows that hot spots with 10,000 light intensity enhancement can be achieved using nano-gap fingers under a resonant wavelength of 638 nm. From cryogenic 1H-NMR spectra, formic acid and acetic acid productions are observed with a nano-fingers array sample. After 1 h laser irradiation, we only observe the generation of formic acid in the liquid solution. While increasing the laser irradiation period, we observe both formic and acetic acid in the liquid solution. We also observe that laser irradiation at different wavelengths significantly affected the generation of formic acid and acetic acid. The ratio, 2.29, of the product concentration generated at the resonant wavelength 638 nm and the non-resonant wavelength 405 nm is close to the ratio, 4.93, of the generated hot electrons inside the TiO2 layer at different wavelengths from the electromagnetics simulation. This shows that product generation is related to the strength of localized electric fields.

Tongqiao Huoxue Decoction ameliorates traumatic brain injury-induced gastrointestinal dysfunction by regulating CD36/15-LO/NR4A1 signaling, which fails when CD36 and CX3CR1 are deficient.

Gastrointestinal (GI) dysfunction, as a common peripheral-organ complication after traumatic brain injury (TBI), is primarily characterized by gut inflammation and damage to the intestinal mucosal barrier (IMB). Previous studies have confirmed that TongQiao HuoXue Decoction (TQHXD) has strong anti-inflammatory properties and protects against gut injury. However, few have reported on the therapeutic effects of TQHXD in a TBI-induced GI dysfunction model. We aimed to explore the effects of TQHXD on TBI-induced GI dysfunction and the underlying mechanism thereof. We assessed the protective effects and possible mechanism of TQHXD in treating TBI-induced GI dysfunction via gene engineering, histological staining, immunofluorescence (IF), 16S ribosomal ribonucleic acid (rRNA) sequencing, real-time polymerase chain reaction (RT-PCR), enzyme-linked immunosorbent assay (ELISA), Western blot (WB), and flow cytometry (FCM). TQHXD administration ameliorated TBI-induced GI dysfunction by modulating the abundance and structure of bacteria; reconstructing the destroyed epithelial and chemical barriers of the IMB; and improving M1/M2 macrophage, T-regulatory cell (Treg)/T helper 1 cell (Th1 ), as well as Th17 /Treg ratios to preserve homeostasis of the intestinal immune barrier. Notably, Cluster of Differentiation 36 (CD36)/15-lipoxygenase (15-LO)/nuclear receptor subfamily 4 group A member 1 (NR4A1) signaling was markedly stimulated in colonic tissue of TQHXD-treated mice. However, insufficiency of both CD36 and (C-X3-C motif) chemokine receptor 1 (CX3CR1) worsened GI dysfunction induced by TBI, which could not be rescued by TQHXD. TQHXD exerted therapeutic effects on TBI-induced GI dysfunction by regulating the intestinal biological, chemical, epithelial, and immune barriers of the IMB, and this effect resulted from the stimulation of CD36/NR4A1/15-LO signaling; however, it could not do so when CX3CR1 and CD36 were deficient. TQHXD might therefore be a potential drug candidate for treating TBI-induced GI dysfunction.

Quantifiable Regulation of Chemical Kinetics Barriers for Creation of Single-Atom Metal Sites on Photocatalytic Atomic Layers

Cation exchange (CE) under mild conditions promises a facile strategy to anchor single metal sites on colloidal chalcogenides toward catalytic applications, which however has seldom been demonstrated. The dilemma behind this is the rapid kinetics and high efficiency of the reaction disfavoring atomic dispersion of the metal species. Here we report that a fine-tuning of the affinity between the incoming metal cations and the deliberately introduced ligands can be exploited to manipulate the kinetics of the CE reaction, in a quantitative and systematic manner defined by the Tolman electronic parameter of the ligands used. Moreover, the steric effect of metal-ligand complexes offers thermodynamic preference for spatial isolation of the metal atoms. These thereby allow the rational construction of single atom catalysts (SACs) via simple one-step CE reactions, as exemplified by the CE-derived incorporation of single metal atoms (M = Cu, Ag, Au, Pd) on SnS2 two-unit-cell layers through M-S coordination.

Effects of chronic stress and intestinal inflammation on commercial poultry health and performance: A review

The gastrointestinal tract provides the biological environment for nutrient digestion and absorption. Its physical and chemical barriers are crucial to protect from invading pathogens and toxic substances. On this basis, the intactness of the gastrointestinal tract, with its multiple functions and impacts, is one of the key prerequisites for human and animal health. Undoubtedly, the functions of a healthy gut system also largely benefit the welfare and performance of animals in farming systems such as poultry industries. Broiler chickens grow rapidly, as a result of rigorous genetic programs, due to the high absorption capacity of intestinal epithelia for nutrients, the quick transport of nutrients to the muscle, and their efficient conversion into energy and biomass. Due to oxygen metabolism or enteric commensal bacteria, intestinal epithelial cells create reactive oxygen and nitrogen species physiologically. However, increased generation of these oxidants goes along with the formation of free radicals resulting in oxidative stress causing lipid peroxidation and dramatic molecular changes in the structure and function of the cell and mitochondrial membranes. These effects contribute to chronic oxidative stress and inflammation of the gastrointestinal tract and generally affect all chicken organs, tissues, and cells. Hence, all forms of chronic stress, regardless of the origin, negatively impact the chicken's overall performance, health, and welfare. This review article highlights some enteric inflammation models and biomarkers to evaluate gut integrity in chickens and discusses the repercussions that chronic stress and intestinal inflammation have on the health and performance of commercial poultry

Effector-mediated partial and nonhost disease resistance in wheat.

Effector-mediated partial and nonhost disease resistance in wheat.

The epithelial barrier theory: Development and exacerbation of allergic and other chronic inflammatory diseases.

It is now longer than half a century, humans, animals, and nature of the world are under the influence of exposure to many newly introduced noxious substances. These exposures are nowadays pushing the borders to be considered as the causative or exacerbating factors for many chronic disorders including allergic, autoimmune/inflammatory, and metabolic diseases. The epithelial linings serve as the outermost body's primary physical, chemical, and immunological barriers against external stimuli. The "epithelial barrier theory" hypothesizes that these diseases are aggravated by an ongoing periepithelial inflammation triggered by exposure to a wide range of epithelial barrier-damaging insults that lead to "epithelitis" and the release of alarmins. A leaky epithelial barrier enables the microbiome's translocation from the periphery to interepithelial and even deeper subepithelial areas together with allergens, toxins, and pollutants. Thereafter, microbial dysbiosis, characterized by colonization of opportunistic pathogen bacteria and loss of the number and biodiversity of commensal bacteria take place. Local inflammation, impaired tissue regeneration, and remodeling characterize the disease. The infiltration of inflammatory cells to affected tissues shows an effort to expulse the tissue invading bacteria, allergens, toxins, and pollutants away from the deep tissues to the surface, representing the "expulsion response." Cells that migrate to other organs from the inflammatory foci may play roles in the exacerbation of various inflammatory diseases in distant organs. The purpose of this review is to highlight and appraise recent opinions and findings on epithelial physiology and its role in the pathogenesis of chronic diseases in view of the epithelial barrier theory.

Oxidation decomposition mechanism of hexamethyldisiloxane

Siloxane working fluid has good environmental performance and thermodynamic performance, widely used in high temperature heat source ORC system. During the filling process of working fluid and operation in ORC system operation, air may leak into the system. The reaction of siloxane working fluid with oxygen in high temperature environment will produce abrasive silica, which will cause serious damage to the system. The oxidative decomposition mechanism of hexamethyldisiloxane (MM) was analyzed by density functional theory (DFT) and ReaxFF molecular dynamic simulation. It is found that the initial reactions of MM oxidation decomposition can be divided into two categories. The first type is the thermal decomposition of MM itself. The second one is the collision reaction between MM molecule and O2 molecule. Comparing the two kinds of chemical reaction barriers, MM is more likely to react with O2. Pathways 2–3 involving the collision between O2 molecule and Si atom are the optimal pathway of initial reaction kinetics, and its reaction energy barrier is 204.1 kJ/mol. It was observed from ReaxFF MD simulations that the main products of MM oxidative decomposition were CH4, CH2O, CO, CO2, SiO and amorphous silica. In the process of oxidative decomposition, small free radicals such as CH3, O, H, OH played a very important role in the oxidative decomposition of working fluids, which greatly promoted the decomposition of working fluids and the formation of main products.

Bifunctional Separator with Ultra-Lightweight MnO2 Coating for Highly Stable Lithium-Sulfur Batteries.

The severe shuttling behavior in the discharging-charging process largely hampers the commercialization of lithium-sulfur (Li-S) batteries. Herein, we design a bifunctional separator with an ultra-lightweight MnO2 coating to establish strong chemical adsorption barriers for shuttling effect alleviation. The double-sided polar MnO2 layers not only trap the lithium polysulfides through extraordinary chemical bonding but also ensure the uniform Li+ flux on the lithium anode and inhibit the side reaction, resulting in homogeneous plating and stripping to avoid corrosion of the Li anode. Consequently, the assembled Li-S battery with the MnO2-modified separator retains a capacity of 665 mA h g-1 at 1 C after 1000 cycles at the areal sulfur loading of 2.5 mg cm-2, corresponding to only 0.028% capacity decay per cycle. Notably, the areal loading of ultra-lightweight MnO2 coating is as low as 0.007 mg cm-2, facilitating the achievement of a high energy density of Li-S batteries. This work reveals that the polar metal oxide-modified separator can effectively inhibit the shuttle effect and protect the Li anode for high-performance Li-S batteries.

Oat β-glucan supplementation pre- and during pregnancy alleviates fetal intestinal immunity development damaged by gestational diabetes in rats.

Oat β-glucan (OG) has been shown to improve intestinal microecology in gestational diabetes mellitus (GDM), but the effect on fetal intestine health is unknown. Herein, we aimed to investigate the effects of OG supplementation during gestation in GDM dams on fetal intestinal immune development. OG was supplemented one week before mating until the end of the experiment. GDM rats were made with a high-fat diet (HFD) with a minimal streptozotocin (STZ) dose. The fetal intestines were sampled at gestation day (GD) 19.5, and the intestinal morphology, chemical barrier molecules, intraepithelial immune cell makers, and levels of inflammatory cytokines were investigated. The results showed that OG supplementation alleviated the decrease of the depth of fetal intestinal villi and crypts, the number of goblet cells (GCs), protein expression of mucin-1 (Muc1) and Muc2, the mRNA levels of Gpr41, Gpr43, and T cell markers, and increased the number of paneth cells (PCs), the mRNA levels of defensin-6 (defa6), and macrophage (Mø) marker and the expression of cytokines induced by GDM. In addition, OG supplementation alleviated the function of immune cell self-proliferation, chemotaxis and assembly capabilities, protein, fat, folic acid, and zinc absorption damaged by GDM. As indicated by these findings, OG supplementation before and during pregnancy improved the fetal intestinal chemical barriers, immune cells, cytokines, and the metabolism of nutrients to protect the fetal intestinal immunity.

Transcriptomics and metabolomics reveal the mechanisms of enhanced constitutive resistance in rice (Oryza Sativa L.) by silica nanomaterials

Silica NMs promoted physical (trichomes, dumbbell-shaped silica cells, and lignin content) and chemical barriers (total phenolics and proline) against pathogen and insects by triggering jasmonic acid and salicylic acid pathways in rice.

Assessment of the role and mechanism of Bifidobacterium animalis subsp. lactis isolated from neonates' feces in protecting neonatal rats from Salmonella infection.

It is now well known that Bifidobacterium animalis subsp. lactis (B. lactis), an important early-life colonizer of the gut, provides immune-related benefits to infants. The aim of the work is to explore the intraspecific resistance to Salmonella infection of B. lactis isolated from neonatal feces, and to learn more insights into how B. lactis mediates beneficial roles in early-life infection resistance. Five strains of B. lactis (NFBAL11/NFBAL23/NFBAL44/NFBAL63/NFBAL92) were screened from fecal samples of neonates born within fifteen days and pretreated neonatal rats prior to infection with Salmonella typhimurium (S. typhimurium) SL1344. The survival rate, fecal occult blood, diarrhea and hepatosplenomegaly were detected to assess the ability of B. lactis to prevent S. typhimurium infection. Furthermore, the structure of mucus layer, gene expression, cytokine levels, antioxidant levels and intestinal microflora composition were detected to explore the mechanism. All strains showed activity against S. typhimurium, with B. lactis NFBAL23 being the most active, followed by NFBAL63 and NFBAL92. And these advantages weren't attained by enhancing physical growth and development. Mechanistically, the neonatal rats treated with B. lactis (NFBAL23/NFBAL63/NFBAL92) had improved intestinal barrier function involving physical, chemical, immune and biological barriers in the face of challenges posed by S. typhimurium. These findings revealed the intraspecific difference, beneficial roles and mechanisms of action of B. lactis against Salmonella infection early in life, which highlighted the necessity of supplementing appropriate B. lactis, and provided several potential B. lactis candidates for Salmonella infection treatment.

Genome-wide association study reveals WRKY42 as a novel plant transcription factor that influences oviposition preference of Pieris butterflies.

Insect herbivores are amongst the most destructive plant pests, damaging both naturally occurring and domesticated plants. As sessile organisms, plants make use of structural and chemical barriers to counteract herbivores. However, over 75% of herbivorous insect species are well adapted to their host's defenses and these specialists are generally difficult to ward off. By actively antagonizing the number of insect eggs deposited on plants, future damage by the herbivore's offspring can be limited. Therefore, it is important to understand which plant traits influence attractiveness for oviposition, especially for specialist insects that are well adapted to their host plants. In this study, we investigated the oviposition preference of Pieris butterflies (Lepidoptera: Pieridae) by offering them the choice between 350 different naturally occurring Arabidopsis accessions. Using a genome-wide association study of the oviposition data and subsequent fine mapping with full genome sequences of 164 accessions, we identified WRKY42 and AOC1 as candidate genes that are associated with the oviposition preference observed for Pieris butterflies. Host plant choice assays with Arabidopsis genotypes impaired in WRKY42 or AOC1 function confirmed a clear role for WRKY42 in oviposition preference of female Pieris butterflies, while for AOC1 the effect was mild. In contrast, WRKY42-impaired plants, which were preferred for oviposition by butterflies, negatively impacted offspring performance. These findings exemplify that plant genotype can have opposite effects on oviposition preference and caterpillar performance. This knowledge can be used for breeding trap crops or crops that are unattractive for oviposition by pest insects.

Differential reinforcement of intestinal barrier function by various Lactobacillus reuteri strains in mice with DSS-induced acute colitis

AimsInflammatory bowel disease is a complex, refractory disorder characterised by chronic gastrointestinal inflammation. Studies have reported that Lactobacillus reuteri alleviates gastrointestinal inflammation and strengthens the intestinal barrier. However, further biochemical and genetic studies are required to correctly understand the therapeutic potential of L. reuteri. Materials and methodsThis study sought to further understand the anti-colitis effect of L. reuteri isolated from faecal samples of healthy locals by focusing on biochemical (immunological, mechanical, chemical and biological barriers) and genetic studies. Key findingsIn this study, we assessed and compared the benefits and efficacy of L. reuteri FYNDL13 and FCQHC8L in the treatment of colitis and found strain FYNDL13 to be superior to FCQHC8L in this regard. Compared with FCQHC8L, FYNDL13 was associated with more diverse and powerful regulatory pathways. Meanwhile, it encouraged butyric acid formation, upregulated antimicrobial peptide-coding gene transcription and prevented hyperimmune reactions on the intestinal periphery and within the intestine. Moreover, it enhanced the abundance of beneficial bacteria (Bifidobacterium, Akkermansia, Blautia and Oscillospira), thereby limiting the relative abundance of harmful bacteria (Bacteroides and Sutterella). Furthermore, the advantage might be attributed to metabolism- and defence system-related genomic characteristics. SignificanceTaken together, our study compares and summarizes a pathway paradigm of these two L. reuteri strains in reinforcing the intestinal barrier against colitis and identifies candidate genes responsible for microbiota-immune axis balance.

Dietary-Polysaccharide-Modified Fish-Oil-Based Double Emulsion as a Functional Colloidal Formulation for Oral Drug Delivery.

Oral delivery is the most convenient drug administration route. However, oral delivery of peptides is extremely challenging due to the physical and chemical barriers within the gastrointestinal tract. Polysaccharides are often utilized as polymeric biomaterials in drug delivery. Among these, dietary polysaccharides extracted from okra, yam, and spirulina have been reported to stimulate innate immunity with well-known nutritional benefits. In this study, we developed a dietary-polysaccharide-modified fish-oil-based emulsion for oral co-delivery of a hydrophilic PD-L1 blocking peptide and the hydrophobic small molecule simvastatin. The optimal emulsion was nano-sized and exhibited a negative surface charge, high drug encapsulation efficiency of over 97%, low viscosity, and sustained drug release manner. The formulation could significantly increase the uptake of peptides by intestinal Caco-2 cells, which demonstrated the great potential of the formulation for promoting the oral absorption of peptides. Additionally, these dietary polysaccharides could promote dendritic cell maturation and cytokine expression in macrophages, demonstrating that these nutraceutical polysaccharides had dual roles of functioning as promising colloidal delivery systems and as potential immune modulators or adjuvants. Thus, this food-based colloidal delivery system shows promise for the oral delivery of peptide drugs and lays a great platform for future applications in immunotherapy.

The Therapeutic Potential of Targeting Key Signaling Pathways as a Novel Approach to Ameliorating Post-Surgical Adhesions.

Peritoneal adhesions (PA) are a common complication of abdominal operations. A growing body of evidence shows that inhibition of inflammation and fibrosis at sites of peritoneal damaging could prevent the development of intra-abdominal adhesions. A search of PubMed, Medline, CINAHL and Embase databases was performed using the keywords 'postsurgical adhesion', 'post-operative adhesion', 'peritoneal adhesion', 'surgery-induced adhesion' and 'abdominal adhesion'. Studies detailing the use of pharmacological and non-pharmacological agents for peritoneal adhesion prevention were identified, and their bibliographies were thoroughly reviewed to identify further related articles. Several signaling pathways, such as tumor necrosis factor-alpha, tissue plasminogen activator, and type 1 plasminogen activator inhibitor, macrophages, fibroblasts, and mesothelial cells play a key part in the development of plasminogen activator. Several therapeutic approaches based on anti-PA drug barriers and traditional herbal medicines have been developed to prevent and treat adhesion formation. In recent years, the most promising method to prevent PA is treatment using biomaterial-based barriers. In this review, we provide an overview of the pathophysiology of adhesion formation and various agents targeting different pathways, including chemical agents, herbal agents, physical barriers, and clinical trials concerning this matter.

Amalgamation of high-κ dielectrics with graphene: A catalyst in the orbit of nanoelectronics and material sciences

In electronics, the size of transistors has been reduced to a few nanometers. Electronic devices’ accuracy and authenticity face a major problem of leakage current. To solve this tricky situation, high-κ dielectrics which have a huge band gap and permittivity are established to increase the capacitance and remove the leakage current. Three major properties are related to current flow: 1) band gap, 2) resistance, and 3) dielectric constant. High-κ or higher dielectric constant shows how much charge a material can hold. A large band gap is needed to vanquish charge injection that causes leakage current. So, these are the insulating materials that store charges when placed in between metallic plates. The dielectric thickness of high-κ can be enhanced without enhancing the capacitance, hence reducing the leakage current. These materials need to be functionalized. Materials with low physical and chemical barriers need to be functionalized with them. The best material to be integrated with these high-κ dielectrics is graphene, as the goal of large area uniformity of electrical properties is achievable with this and easily separable graphene is also available. Here, we will scrutinize the current advancement in graphene electronics-based research on high-κ dielectrics such as Al₂O₃ (used as obstructing oxide in charge trap flash memory) with graphene. This article reviews the amalgamation of oxides such as high-κ dielectrics with graphene, which are necessary for the understanding of top-gated electronic devices made by graphene which includes field-effect transistors and other electronic devices.