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High-throughput computational materials discovery has promised significant acceleration of the design and discovery of new materials for many years. Despite a surge in interest and activity, the constraints imposed by large-scale computational resources present a significant bottleneck. Furthermore, examples of very large-scale computational discovery carried out through experimental validation remain scarce, especially for materials with product applicability. Here, we demonstrate how this vision became reality by combining state-of-the-art machine learning (ML) models and traditional physics-based models on cloud high-performance computing (HPC) resources to quickly navigate through more than 32 million candidates and predict around half a million potentially stable materials. By focusing on solid-state electrolytes for battery applications, our discovery pipeline further identified 18 promising candidates with new compositions and rediscovered a decade's worth of collective knowledge in the field as a byproduct. We then synthesized and experimentally characterized the structures and conductivities of our top candidates, the NaxLi3-xYCl6 (0≤ x≤ 3) series, demonstrating the potential of these compounds to serve as solid electrolytes. Additional candidate materials that are currently under experimental investigation could offer more examples of the computational discovery of new phases of Li- and Na-conducting solid electrolytes. The showcased screening of millions of materials candidates highlights the transformative potential of advanced ML and HPC methodologies, propelling materials discovery into a new era of efficiency and innovation.
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Nonstoichiometric lead oxides play a key role in the formation and cycling of the positive electrodes in a lead acid battery. These phases have been linked to the underutilization of the positive active material but also play a key role in the battery's cycle life, providing interparticle adhesion and the connection to the underlying lead grid. Similar phases have previously been identified by mass loss or color change during thermal annealing of PbO2 to PbO, suggesting that at least two intermediate PbOx phases exist. Using multiple, in situ analysis techniques (powder diffraction, X-ray absorption, X-ray photoelectron spectroscopy) and ex situ nuclear magnetic resonance measurements, the structural conversion and changes in the lead oxidation state were identified during this process. Isolation of the PbOx phases enabled confirmation of Pb3O5 and Pb2O3 by diffraction and the first 207Pb NMR measurement of these intermediates. The thermodynamic and kinetic stability of these intermediates and other reported polymorphs were determined by density functional theory, providing key insight into their origins and variation of PbOx structures found in previous studies.
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Carbon-based nanomaterials, including graphene, fullerenes, and carbon nanotubes, are attracting significant attention as promising materials for next-generation energy storage and conversion applications. They possess unique physicochemical properties, such as structural stability and flexibility, high porosity, and tunable physicochemical features, which render them well suited in these hot research fields. Technological advances at atomic and electronic levels are crucial for developing more efficient and durable devices. This comprehensive review provides a state-of-the-art overview of these advanced carbon-based nanomaterials for various energy storage and conversion applications, focusing on supercapacitors, lithium as well as sodium-ion batteries, and hydrogen evolution reactions. Particular emphasis is placed on the strategies employed to enhance performance through nonmetallic elemental doping of N, B, S, and P in either individual doping or codoping, as well as structural modifications such as the creation of defect sites, edge functionalization, and inter-layer distance manipulation, aiming to provide the general guidelines for designing these devices by the above approaches to achieve optimal performance. Furthermore, this review delves into the challenges and future prospects for the advancement of carbon-based electrodes in energy storage and conversion.
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Fontes de Energia Elétrica , Carbono/química , Eletrodos , Transferência de Energia , Nanotubos de Carbono/química , Pontos Quânticos , Grafite/química , Condutividade Elétrica , Lítio/química , Técnicas Eletroquímicas , Sódio/química , CatáliseRESUMO
The design of novel drug delivery systems is exceptionally critical in disease treatments. Among the existing drug delivery systems, mesoporous silica nanoparticles (MSNs) have shown profuse promise owing to their structural stability, tunable morphologies/sizes, and ability to load different payload chemistry. Significantly, the presence of surface silanol groups enables functionalization with relevant drugs, imaging, and targeting agents, promoting their utility and popularity among researchers. Stimuli-responsive silanol conjugates have been developed as a novel, more effective way to conjugate, deliver, and release therapeutic drugs on demand and precisely to the selected location. Therefore, it is urgent to summarize the current understanding and the surface silanols' role in making MSN a versatile drug delivery platform. This review provides an analytical understanding of the surface silanols, chemistry, identification methods, and their property-performance correlation. The chemistry involved in converting surface silanols to a stimuli-responsive silica delivery system by endogenous/exogenous stimuli, including pH, redox potential, temperature, and hypoxia, is discussed in depth. Different chemistries for converting surface silanols to stimuli-responsive bonds are discussed in the context of drug delivery. The critical discussion is culminated by outlining the challenges in identifying silanols' role and overcoming the limitations in synthesizing stimuli-responsive mesoporous silica-based drug delivery systems.
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Solar-driven photothermal water evaporation is considered an elegant and sustainable technology for freshwater production. The existing systems, however, often suffer from poor stability and biofouling issues, which severely hamper their prospects in practical applications. Conventionally, photothermal materials are deposited on the membrane supports via vacuum-assisted filtration or dip-coating methods. Nevertheless, the weak inherent material-membrane interactions frequently lead to poor durability, and the photothermal material layer can be easily peeled off from the hosting substrates or partially dissolved when immersed in water. In the present article, the discovery of the incorporation of borophene into cellulose nanofibers (CNF), enabling excellent environmental stability with a high light-to-heat conversion efficiency of 91.5% and water evaporation rate of 1.45 kg m-2 h-1 under simulated sunlight is reported. It is also demonstrated that borophene papers can be employed as an excellent active photothermal material for eliminating almost 100% of both gram-positive and gram-negative bacteria within 20 min under three sun irradiations. The result opens a new direction for the design of borophene-based papers with unique photothermal properties which can be used for the effective treatment of a wide range of wastewaters.
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Bactérias Gram-Negativas , Água , Antibacterianos , Bactérias Gram-Positivas , CeluloseRESUMO
Carbon-based quantum dots (QDs) have emerged as a fascinating class of advanced materials with a unique combination of optoelectronic, biocompatible, and catalytic characteristics, apt for a plethora of applications ranging from electronic to photoelectrochemical devices. Recent research works have established carbon-based QDs for those frontline applications through improvements in materials design, processing, and device stability. This review broadly presents the recent progress in the synthesis of carbon-based QDs, including carbon QDs, graphene QDs, graphitic carbon nitride QDs and their heterostructures, as well as their salient applications. The synthesis methods of carbon-based QDs are first introduced, followed by an extensive discussion of the dependence of the device performance on the intrinsic properties and nanostructures of carbon-based QDs, aiming to present the general strategies for device designing with optimal performance. Furthermore, diverse applications of carbon-based QDs are presented, with an emphasis on the relationship between band alignment, charge transfer, and performance improvement. Among the applications discussed in this review, much focus is given to photo and electrocatalytic, energy storage and conversion, and bioapplications, which pose a grand challenge for rational materials and device designs. Finally, a summary is presented, and existing challenges and future directions are elaborated.
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Nanoceria has evolved as a promising nanomaterial due to its unique enzyme-like properties, including excellent oxidase mimetic activity, which significantly increases in the presence of fluoride ions. However, this significant increase in oxidase activity has never been utilised as a signal enhancer for the detection of biological analytes partly because of the lack of understanding of the mechanism involved in this process. In this study, we show that the surface oxidation state of cerium ions plays a very crucial role in different enzymatic activities, especially the oxidase mimetic activity by engineering nanoceria with three different surface Ce4+/Ce3+ compositions. Using DFT calculations combined with Bader charge analysis, it is demonstrated that stoichiometric ceria registers a higher oxidase mimetic activity than oxygen-deficient ceria with a low Ce4+/Ce3+ ratio due to a higher charge transfer from a substrate, 3,3',5,5' tetramethylbenzidine (TMB), to the ceria surface. We also show that the fluoride ions can significantly increase the charge transfer from the TMB surface to ceria irrespective of the surface Ce4+/Ce3+ ratio. Using this knowledge, we first compare the fluoride sensing properties of nanoceria with high Ce4+ and mixed Ce4+/Ce3+ oxidation states and further demonstrate that the linear detection range of fluoride ions can be extended to 1-10 ppm for nanoceria with mixed oxidation states. Then, we also demonstrate an assay for fluoride assisted detection of glutathione, an antioxidant with elevated levels during cancer, using nanoceria with a high surface Ce4+/Ce3+ ratio. The addition of fluoride ions in this assay allows the detection of glutathione in the linear range of 2.5-50 ppm with a limit of detection (LOD) of 3.8 ppm. These studies not only underpin the role of the surface Ce4+/Ce3+ ratio in tuning the fluoride assisted boost in the oxidase mimetic activity of nanoceria but also its strategic application in designing better colourimetric assays.
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Fluoretos , Glutationa , Teoria da Densidade Funcional , OxirredutasesRESUMO
Organoid technology has provided unique insights into human organ development, function, and diseases. Patient-derived organoids are increasingly used for drug screening, modeling rare disorders, designing regenerative therapies, and understanding disease pathogenesis. However, the use of Matrigel to grow organoids represents a major challenge in the clinical translation of organoid technology. Matrigel is a poorly defined mixture of extracellular matrix proteins and growth factors extracted from the Engelbreth-Holm-Swarm mouse tumor. The extracellular matrix is a major driver of multiple cellular processes and differs significantly between tissues as well as in healthy and disease states of the same tissue. Therefore, we envisioned that the extracellular matrix derived from a native healthy tissue would be able to support organoid growth akin to organogenesis in vivo. Here, we have developed hydrogels from decellularized human and bovine endometrium. These hydrogels supported the growth of mouse and human endometrial organoids, which was comparable to Matrigel. Organoids grown in endometrial hydrogels were proteomically more similar to the native tissue than those cultured in Matrigel. Proteomic and Raman microspectroscopy analyses showed that the method of decellularization affects the biochemical composition of hydrogels and, subsequently, their ability to support organoid growth. The amount of laminin in hydrogels correlated with the number and shape of organoids. We also demonstrated the utility of endometrial hydrogels in developing solid scaffolds for supporting high-throughput, cell culture-based applications. In summary, endometrial hydrogels overcome a major limitation of organoid technology and greatly expand the applicability of organoids to understand endometrial biology and associated pathologies.
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Neoplasias , Organoides , Feminino , Humanos , Bovinos , Animais , Organoides/metabolismo , Hidrogéis/química , Laminina/farmacologia , Laminina/metabolismo , Proteômica , Endométrio , Neoplasias/metabolismoRESUMO
Lung cancer is one of the most common cancers, affecting more than 2.1 million people across the globe every year. A very high occurrence and mortality rate of lung cancer have prompted active research in this area with both conventional and novel forms of therapies including the use of nanomaterials based drug delivery agents. Specifically, the unique physico-chemical and biological properties of porous nanomaterials have gained significant momentum as drug delivery agents for delivering a combination of drugs or merging diagnosis with targeted therapy for cancer treatment. This review focuses on the emergence of nano-porous materials for drug delivery in lung cancer. The review analyses the currently used nanoporous materials, including inorganic, organic and hybrid porous materials for delivering drugs for various types of therapies, including chemo, radio and phototherapy. It also analyses the selected research on stimuli-responsive nanoporous materials for drug delivery in lung cancer before summarizing the various findings and projecting the future of emerging trends. This review provides a strong foundation for the current status of the research on nanoporous materials, their limitations and the potential for improving their design to overcome the unique challenges of delivering drugs for the treatment of lung cancer.
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Müllerian ducts are paired tubular structures that give rise to most of the female reproductive organs. Any abnormalities in the development and differentiation of these ducts lead to anatomical defects in the female reproductive tract organs categorized as Müllerian duct anomalies. Due to the limited access to fetal tissues, little is understood of human reproductive tract development and the associated anomalies. Although organoids represent a powerful model to decipher human development and disease, such organoids from fetal reproductive organs are not available. Here, we developed organoids from human fetal fallopian tubes and uteri and compared them with their adult counterparts. Our results demonstrate that human fetal reproductive tract epithelia do not express some of the typical markers of adult reproductive tract epithelia. Furthermore, fetal organoids are grossly, histologically, and proteomically different from adult organoids. While external supplementation of WNT ligands or activators in culture medium is an absolute requirement for the adult reproductive tract organoids, fetal organoids are able to grow in WNT-deficient conditions. We also developed decellularized tissue scaffolds from adult human fallopian tubes and uteri. Transplantation of fetal organoids onto these scaffolds led to the regeneration of the adult fallopian tube and uterine epithelia. Importantly, suppression of Wnt signaling, which is altered in patients with Müllerian duct anomalies, inhibits the regenerative ability of human fetal organoids and causes severe anatomical defects in the mouse reproductive tract. Thus, our fetal organoids represent an important platform to study the underlying basis of human female reproductive tract development and diseases.
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Tubas Uterinas , Ductos Paramesonéfricos , Organoides , Útero , Adulto , Animais , Tubas Uterinas/crescimento & desenvolvimento , Feminino , Feto , Humanos , Ligantes , Camundongos , Ductos Paramesonéfricos/anormalidades , Organoides/crescimento & desenvolvimento , Organoides/metabolismo , Útero/crescimento & desenvolvimento , Via de Sinalização WntRESUMO
With the threat of increasing SARS-CoV-2 cases looming in front of us and no effective and safest vaccine available to curb this pandemic disease due to its sprouting variants, many countries have undergone a lockdown 2.0 or planning a lockdown 3.0. This has upstretched an unprecedented demand to develop rapid, sensitive, and highly selective diagnostic devices that can quickly detect coronavirus (COVID-19). Traditional techniques like polymerase chain reaction have proven to be time-inefficient, expensive, labor intensive, and impracticable in remote settings. This shifts the attention to alternative biosensing devices that can be successfully used to sense the COVID-19 infection and curb the spread of coronavirus cases. Among these, nanomaterial-based biosensors hold immense potential for rapid coronavirus detection because of their noninvasive and susceptible, as well as selective properties that have the potential to give real-time results at an economical cost. These diagnostic devices can be used for mass COVID-19 detection to understand the rapid progression of the infection and give better-suited therapies. This review provides an overview of existing and potential nanomaterial-based biosensors that can be used for rapid SARS-CoV-2 diagnostics. Novel biosensors employing different detection mechanisms are also highlighted in different sections of this review. Practical tools and techniques required to develop such biosensors to make them reliable and portable have also been discussed in the article. Finally, the review is concluded by presenting the current challenges and future perspectives of nanomaterial-based biosensors in SARS-CoV-2 diagnostics.
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Cerium oxide nanoparticles (CeNPs) exhibit excellent in vitro and in vivo antioxidant properties, determined by the redox switching of surface cerium ions between their two oxidation states (Ce3+ and Ce4+). It is known that ligands such as triethyl phosphite (TEP) can tune the redox behavior of CeNPs and change their biological enzyme-mimetic activities; however, the corresponding mechanism for such a behavior is completely unknown. Herein, we have studied the effect of TEP in promoting the SOD-enzyme-like activity in CeNPs with high and low Ce3+/Ce4+ ratio, which were synthesized by wet chemical and thermal hydrolysis methods, respectively, and incubated with varying concentrations of TEP. X-ray diffraction, UV-visible, photoluminescence, X-ray photoelectron spectroscopy, and Raman spectroscopy combined with DFT calculations were used to investigate the interaction of TEP on the surface of CeNPs. We observed a clear correlation between TEP concentration and the formation of surface oxygen vacancies. XPS analysis confirmed the increase in Ce3+ concentration after interaction with TEP. Moreover, we show that TEP's influence depends on the surface Ce3+/Ce4+ ratio. The superoxide dismutase-, catalase-, and oxidase-like activities of CeNPs with high Ce3+/Ce4+ ratio are not affected by TEP interaction, whereas catalase- and oxidase-like activities of CeNPs with low Ce3+/Ce4+ ratio decrease and the SOD-like activity is found to increase upon incubation with different concentrations of TEP. We also demonstrate that TEP interaction does not affect the regeneration of the CeNP surface, while the DFT calculations show that TEP facilitates the formation of defects on the surface of stoichiometric cerium oxide by reducing the oxygen vacancy formation energy. CeNPs with low Ce3+/Ce4+ ratio incubated with TEP also exhibited good antibacterial activity as compared to the CeNPs or TEP alone.
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Cério , Nanopartículas , Catalase/química , Cério/química , Ligantes , Nanopartículas/química , Oxigênio , Fosfitos , Superóxido Dismutase/químicaRESUMO
Mesoporous silica-based nanoparticles (MSNs) have gained rapid interest as a drug delivery system (DDS) and demonstrated their versatility in delivering drugs for the treatment of various cancers. However, the drug loading efficiency of MSNs is low and is usually improved by improving textural properties through complicated synthesis methods or by post synthesis modification of the surface that can result in the loss of surface area and modify its drug release properties. In this study, we report a direct single-step synthesis of MSNs with a unique egg-yolk core-shell morphology, large pore volume and a hydrophilic surface, decorated with nitrogen rich surface functionalities for increasing its drug loading capacity. This combination of excellent textural properties and surface functionalisation was achieved by a simple soft templating method using dual surfactants and the silica sources assisted by employing either triethylamine (TEA) or triethanolamine (TEO) as the hydrolysis agent. The morphology and well-ordered mesoporous structure can simply be tuned by changing the pH of the synthesis medium that affects the self-assembly mechanism of the micelles. HRTEM image of samples clearly revealed an egg-yolk core-shell morphology with a thin mesoporous silica shell. The optimised MSN samples synthesized at a pH of 11 using either TEA or TEO depicted a higher doxorubicin (Dox) loading capacity of 425 µg mg-1 and 481 µg mg-1 respectively, as compared to only 347 µg mg-1 for MSN samples due to the uniform distribution of nitrogen functionalities. The anticancer activity of Dox loaded MSNs evaluated in two different prostate cancer cell lines (PC-3 and LNCaP) showed a higher cytotoxicity of the drug loaded on optimised MSN samples as compared to pristine MSNs without affecting the cellular uptake of the particles. These results suggest that the unique single-step synthesis and functionalisation method resulted in successfully achieving higher drug loading in egg-yolk core-shell nitrogen functionalised MSNs and could be implemented as an effective carrier of chemotherapeutic drugs.
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Nanopartículas , Neoplasias da Próstata , Doxorrubicina/química , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Humanos , Masculino , Nanopartículas/química , Nitrogênio , Porosidade , Neoplasias da Próstata/tratamento farmacológico , Dióxido de Silício/químicaRESUMO
The over-dependence on fossil fuels is one of the critical issues to be addressed for combating greenhouse gas emissions. Hydrogen, one of the promising alternatives to fossil fuels, is renewable, carbon-free, and non-polluting gas. The complete utilization of hydrogen in every sector ranging from small to large scale could hugely benefit in mitigating climate change. One of the key aspects of the hydrogen sector is its production via cost-effective and safe ways. Electrolysis and photocatalysis are well-known processes for hydrogen production and their efficiency relies on electrocatalysts, which are generally noble metals. The usage of noble metals as catalysts makes these processes costly and their scarcity is also a limiting factor. Metal nitrides and their porous counterparts have drawn considerable attention from researchers due to their good promise for hydrogen production. Their properties such as active metal centres, nitrogen functionalities, and porous features such as surface area, pore-volume, and tunable pore size could play an important role in electrochemical and photocatalytic hydrogen production. This review focuses on the recent developments in metal nitrides from their synthesis methods point of view. Much attention is given to the emergence of new synthesis techniques, methods, and processes of synthesizing the metal nitride nanostructures. The applications of electrochemical and photocatalytic hydrogen production are summarized. Overall, this review will provide useful information to researchers working in the field of metal nitrides and their application for hydrogen production.
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Engineered nanomaterials (ENMs) are at the forefront of many technological breakthroughs in science and engineering. The extensive use of ENMs in several consumer products has resulted in their release to the aquatic environment. ENMs entering the aquatic ecosystem undergo a dynamic transformation as they interact with organic and inorganic constituents present in aquatic environment, specifically abiotic factors such as NOM and clay minerals, and attain an environmental identity. Thus, a greater understanding of ENM-abiotic factors interactions is required for an improved risk assessment and sustainable management of ENMs contamination in the aquatic environment. This review integrates fundamental aspects of ENMs transformation in aquatic environment as impacted by abiotic factors, and delineates the recent advances in bioavailability and ecotoxicity of ENMs in relation to risk assessment for ENMs-contaminated aquatic ecosystem. It specifically discusses the mechanism of transformation of different ENMs (metals, metal oxides and carbon based nanomaterials) following their interaction with the two most common abiotic factors NOM and clay minerals present within the aquatic ecosystem. The review critically discusses the impact of these mechanisms on the altered ecotoxicity of ENMs including the impact of such transformation at the genomic level. Finally, it identifies the gaps in our current understanding of the role of abiotic factors on the transformation of ENMs and paves the way for the future research areas.
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Ecossistema , Nanoestruturas , Metais , Nanoestruturas/toxicidadeRESUMO
Mesoporous carbon nitrides with C3 N5 and C3 N6 stoichiometries created a new momentum in the field of organic metal-free semiconductors owing to their unique band structures and high basicity. Here, we report on the preparation of a novel graphitic microporous carbon nitride with a tetrazine based chemical structure and the composition of C3 N5.4 using ultra-stable Y zeolite as the template and aminoguanidine hydrochloride, a high nitrogen-containing molecule, as the CN precursor. Spectroscopic characterization and density functional theory calculations reveal that the prepared material exhibits a new molecular structure, which comprises two tetrazines and one triazine rings in the unit cell and is thermodynamically stable. The resultant carbon nitride shows an outstanding surface area of 130.4â m2 g-1 and demonstrates excellent CO2 adsorption per unit surface area of 47.54â µmol m-2 , which is due to the existence of abundant free NH2 groups, basic sites and microporosity. The material also exhibits highly selective sensing over water molecules (151.1â mmol g-1 ) and aliphatic hydrocarbons due to its unique microporous structure with a high amount of hydrophilic nitrogen moieties and recognizing ability towards small molecules.
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Research on cerium oxide nanoparticles (nanoceria) has captivated the scientific community due to their unique physical and chemical properties, such as redox activity and oxygen buffering capacity, which made them available for many technical applications, including biomedical applications. The redox mimetic antioxidant properties of nanoceria have been effective in the treatment of many diseases caused by reactive oxygen species (ROS) and reactive nitrogen species. The mechanism of ROS scavenging activity of nanoceria is still elusive, and its redox activity is controversial due to mixed reports in the literature showing pro-oxidant and antioxidant activity. In light of its current research interest, it is critical to understand the behavior of nanoceria in the biological environment and provide answers to some of the critical and open issues. This review critically analyzes the status of research on the application of nanoceria to treat diseases caused by ROS. It reviews the proposed mechanism of action and shows the effect of surface coatings on its redox activity. It also discusses some of the crucial issues in deciphering the mechanism and redox activity of nanoceria and suggests areas of future research.
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Cério , Nanopartículas , Oxirredução , Espécies Reativas de OxigênioRESUMO
Prostate cancer (PCa) is one of the most commonly diagnosed cancers and is the fifth common cause of cancer-related mortality in men. Current methods for PCa treatment are insufficient owing to the challenges related to the non-specificity, instability and side effects caused by the drugs and therapy agents. These drawbacks can be mitigated by the design of a suitable drug delivery system that can ensure targeted delivery and minimise side effects. Silica based nanoparticles (SBNPs) have emerged as one of the most versatile materials for drug delivery due to their tunable porosities, high surface area and tremendous capacity to load various sizes and chemistry of drugs. This review gives a brief overview of the diagnosis and current treatment strategies for PCa outlining their existing challenges. It critically analyzes the design, development and application of pure, modified and hybrid SBNPs based drug delivery systems in the treatment of PCa, their advantages and limitations.
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Antineoplásicos/farmacologia , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Neoplasias da Próstata/tratamento farmacológico , Dióxido de Silício/química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Portadores de Fármacos/química , Humanos , Masculino , Neoplasias da Próstata/patologiaRESUMO
Cerium oxide nanoparticles have been shown to mimic oxidoreductase enzymes by catalyzing the decomposition of organic substrates and reactive oxygen species. This mimicry can be found in superoxide radicals and hydrogen peroxides, which are harmful molecules produced in oxidative stress-associated diseases. Despite the fact that nanoparticle functionalization is mandatory in the context of nanomedicine, the influence of polymer coatings on their enzyme-like catalytic activity is poorly understood. In this work, six polymer-coated cerium oxide nanoparticles are prepared by the association of 7.8 nm cerium oxide cores with two poly(sodium acrylate) and four poly(ethylene glycol) (PEG)-grafted copolymers with different terminal or anchoring end groups, such as phosphonic acids. The superoxide dismutase-, catalase-, peroxidase-, and oxidase-like catalytic activities of the coated nanoparticles were systematically studied. It is shown that the polymer coatings do not affect the superoxide dismutase-like, impair the catalase-like and oxidase-like, and surprisingly improves peroxidase-like catalytic activities of cerium oxide nanoparticles. It is also demonstrated that the particles coated with the PEG-grafted copolymers perform better than the poly(acrylic acid)-coated ones as oxidoreductase-like enzymes, a result that confirms the benefit of having phosphonic acids as anchoring groups at the particle surface.
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Resinas Acrílicas/química , Cério/química , Nanopartículas/química , Polietilenoglicóis/química , Catalase/química , Catalase/metabolismo , Catálise , Oxirredutases/química , Oxirredutases/metabolismo , Tamanho da Partícula , Peroxidase/química , Peroxidase/metabolismo , Espécies Reativas de Oxigênio/química , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/química , Superóxido Dismutase/metabolismo , Propriedades de SuperfícieRESUMO
The presence of an excessive concentration of CO2 in the atmosphere needs to be curbed with suitable measures including the reduction of CO2 emissions at stationary point sources such as power plants through carbon capture technologies and subsequent conversion of the captured CO2 into non-polluting clean fuels/chemicals using photo and/or electrocatalytic pathways. Porous materials have attracted much attention for carbon capture and in the recent past; they have witnessed significant advancements in their design and implementation for CO2 capture and conversion. In this context, the emerging trends in major porous adsorbents such as MOFs, zeolites, POPs, porous carbons, and mesoporous materials for CO2 capture and conversion are discussed. Their surface texture and chemistry, and the influence of various other features on their efficiency, selectivity, and recyclability for CO2 capture and conversion are explained and compared thoroughly. The scientific and technical advances on the material structure versus CO2 capture and conversion provide deep insights into designing effective porous materials. The review concludes with a summary, which compiles the key challenges in the field, current trends and critical challenges in the development of porous materials, and future research directions combined with possible solutions for realising the deployment of porous materials in CO2 capture and conversion.