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1.
Small ; : e2402317, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38988143

RESUMO

Here, the poly (l-lactic acid) (PLLA) membrane with multi-structured networks (MSN) is successfully prepared by electrospinning technology for the first time. It is composed of micron-sized ribbon-structured fibers and ultrafine nanofibers with a diameter of tens of nanometers, and they are connected to form the new network structure. Thanks to the special fiber morphology and structure, the interception and electrostatic adsorption ability for against atmospheric particulate matter (PM) are significantly enhanced, and the resistance to airflow is reduced due to the "slip effect" caused by ultrafine nanofibers. The PLLA MSN membrane shows excellent filtration performance with ultra-high filtration efficiency (>99.9% for PM2.5 and >99.5% for PM0.3) and ultra-low pressure drop (≈20 Pa). It has demonstrated filtration performance that even exceeds current non-biodegradable polymer materials, laying the foundation for future applications of biodegradable PLLA in the field of air filtration. In addition, this new structure also provides a new idea for optimizing the performance of other polymer materials.

2.
Chem Rec ; 24(6): e202400030, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38837295

RESUMO

Biomass resources are often disposed of inefficiently and it causes environmental degradation. These wastes can be turned into bio-products using effective conversion techniques. The synthesis of high-value bio-products from biomass adheres to the principles of a sustainable circular economy in a variety of industries, including agriculture. Recently, fluorescent carbon dots (C-dots) derived from biowastes have emerged as a breakthrough in the field, showcasing outstanding fluorescence properties and biocompatibility. The C-dots exhibit unique quantum confinement properties due to their small size, contributing to their exceptional fluorescence. The significance of their fluorescent properties lies in their versatile applications, particularly in bio-imaging and energy devices. Their rapid and straight-forward production using green/chemical precursors has further accelerated their adoption in diverse applications. The use of green precursors for C-dot not only addresses the biomass disposal issue through a scientific approach, but also establishes a path for a circular economy. This approach not only minimizes biowaste, which also harnesses the potential of fluorescent C-dots to contribute to sustainable practices in agriculture. This review explores recent developments and challenges in synthesizing high-quality C-dots from agro-residues, shedding light on their crucial role in advancing technologies for a cleaner and more sustainable future.


Assuntos
Biomassa , Carbono , Pontos Quânticos , Carbono/química , Pontos Quânticos/química , Corantes Fluorescentes/química
3.
Angew Chem Int Ed Engl ; 63(16): e202400888, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38419146

RESUMO

Alkaline water electrolysis (AWE) plays a crucial role in the realization of a hydrogen economy. The design and development of efficient and stable bifunctional catalysts for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are pivotal to achieving high-efficiency AWE. Herein, WC1-x/Mo2C nanoparticle-embedded carbon nanofiber (WC1-x/Mo2C@CNF) with abundant interfaces is successfully designed and synthesized. Benefiting from the electron transfer behavior from Mo2C to WC1-x, the electrocatalysts of WC1-x/Mo2C@CNF exhibit superior HER and OER performance. Furthermore, when employed as anode and cathode in membrane electrode assembly devices, the WC1-x/Mo2C@CNF catalyst exhibits enhanced catalytic activity and remarkable stability for 100 hours at a high current density of 200 mA cm-2 towards overall water splitting. The experimental characterizations and theoretical simulation reveal that modulation of the d-band center for WC1-x/Mo2C@CNF, achieved through the asymmetric charge distribution resulting from the built-in electric field induced by work function, enables optimization of adsorption strength for hydrogen/oxygen intermediates, thereby promoting the catalytic kinetics for overall water splitting. This work provides promising strategies for designing highly active catalysts in energy conversion fields.

4.
Small ; 19(49): e2304086, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37612815

RESUMO

Space charge transfer of heterostructures driven by the work-function-induced built-in field can regulate the electronic structure of catalysts and boost the catalytic activity. Herein, an epitaxial heterojunction catalyst of CoO/Mo2 C with interfacial electron redistribution induced by work functions (WFs) is constructed for overall water splitting via a novel top-down strategy. Theoretical simulations and experimental results unveil that the WFs-induced built-in field facilitates the electron transfer from CoO to Mo2 C through the formed "Co─C─Mo" bond at the interface of CoO/Mo2 C, achieving interfacial electron redistribution, further optimizing the Gibbs free energy of primitive reaction step and then accelerating kinetics of hydrogen evolution reaction (HER). As expected, the CoO/Mo2 C with interfacial effects exhibits excellent HER catalytic activity with only needing the overpotential of 107 mV to achieve 10 mA cm-2 and stability for a 60-h continuous catalyzing. Besides, the assembled CoO/Mo2 C behaves the outstanding performance toward overall water splitting (1.58 V for 10 mA cm-2 ). This work provides a novel possibility of designing materials based on interfacial effects arising from the built-in field for application in other fields.

5.
Inorg Chem ; 62(40): 16547-16553, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37738623

RESUMO

Carbon-supported zinc single-atom catalysts have received considerable attention in the electrocatalytic oxygen reduction reaction (ORR) owing to the strong reduction capacity of zinc atoms and the abundant reserves of zinc elements. The common preparation method has been limited to the high-temperature pyrolysis of nitrogen-rich organic molecules and zinc ions, which makes it difficult to further improve the ORR performance. Herein, we first prepared ZnO/PNT/rGO aerogels as precursors via a simple hydrothermal method combined with freeze-drying, in which reduced graphene oxides (rGO) and polypyrrole nanotubes (PNT) together assembled into three-dimensional frames and numerous ZnO nanoparticles were anchored in the three-dimensional skeletons. Then, ZnO/PNT/rGO aerogels were calcined at 800 °C in the argon atmosphere, in which PNT/rGO were derived carbon aerogels, ZnO nanoparticles were reduced to Zn0 by carbon, and generating zinc single atoms were captured by the surrounding nitrogen atoms or aggregated into Zn clusters/nanoparticles in the carbon substrates. The obtained products were Zn single atoms/clusters/nanoparticles embedded into PNT/rGO-derived carbon aerogels, named Zn/NC catalysts. Zn/NC catalysts display a much higher half-wave potential and a larger limiting current density than pure rGO aerogels, NC, and Zn/C catalysts, indicating the synergy of excellent electronic transportation, high mass efficiency from outstanding porosity, and several active centers. Tailoring the quantity of zinc acetate can provide the optimal ORR performance with the Eonset of 0.96 V, the E1/2 of 0.845 V, and remarkable durability. This work exploits a novel strategy of carbon thermal reduction to construct high-performance Zn-based low-dimensional ORR catalysts.

6.
Environ Res ; 231(Pt 1): 115988, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37105296

RESUMO

Plastics have become an integral part of human life. Single-use plastics (SUPs) are disposable plastics designed to be used once then promptly discarded or recycled. This SUPs range from packaging and takeaway containers to disposable razors and hotel toiletries. Synthetic plastics, which are made of non-renewable petroleum and natural gas resources, require decades to perpetually disintegrate in nature thus contribute to plastic pollution worldwide, especially in marine environments. In response to these problems, bioplastics or bio-based and biodegradable polymers from renewable sources has been considered as an alternative. Understanding the mechanisms behind the degradation of conventional SUPs and biodegradability of their greener counterpart, bioplastics, is crucial for appropriate material selection in the future. This review aims to provide insights into the degradation or disintegration of conventional single-use plastics and the biodegradability of the different types of greener-counterparts, bioplastics, their mechanisms, and conditions. This review highlights on the biodegradation in the environments including composting systems. Here, the various types of alternative biodegradable polymers, such as bacterially biosynthesised bioplastics, natural fibre-reinforced plastics, starch-, cellulose-, lignin-, and soy-based polymers were explored. Review of past literature revealed that although bioplastics are relatively eco-friendly, their natural compositions and properties are inconsistent. Furthermore, the global plastic market for biodegradable plastics remains relatively small and require further research and commercialization efforts, especially considering the urgency of plastic and microplastic pollution as currently critical global issue. Biodegradable plastics have potential to replace conventional plastics as they show biodegradation ability under real environments, and thus intensive research on the various biodegradable plastics is needed to inform stakeholders and policy makers on the appropriate response to the gradually emerging biodegradable plastics.


Assuntos
Plásticos Biodegradáveis , Plásticos , Humanos , Polímeros , Lignina , Biodegradação Ambiental , Amido
7.
J Mater Sci Mater Med ; 34(12): 62, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37982917

RESUMO

3D printing technology is an emerging method that gained extensive attention from researchers worldwide, especially in the health and medical fields. Biopolymers are an emerging class of materials offering excellent properties and flexibility for additive manufacturing. Biopolymers are widely used in biomedical applications in biosensing, immunotherapy, drug delivery, tissue engineering and regeneration, implants, and medical devices. Various biodegradable and non-biodegradable polymeric materials are considered as bio-ink for 3d printing. Here, we offer an extensive literature review on the current applications of synthetic biopolymers in the field of 3D printing. A trend in the publication of biopolymers in the last 10 years are focused on the review by analyzing more than 100 publications. Their application and classification based on biodegradability are discussed. The various studies, along with their practical applications, are elaborated in the subsequent sections for polyethylene, polypropylene, polycaprolactone, polylactide, etc. for biomedical applications. The disadvantages of various biopolymers are discussed, and future perspectives like combating biocompatibility problems using 3D printed biomaterials to build compatible prosthetics are also discussed and the potential application of using resin with the combination of biopolymers to build customized implants, personalized drug delivery systems and organ on a chip technologies are expected to open a new set of chances for the development of healthcare and regenerative medicine in the future.


Assuntos
Membros Artificiais , Impressão Tridimensional , Biopolímeros , Polietileno , Polímeros , Polipropilenos/química
8.
Int J Mol Sci ; 24(4)2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36834721

RESUMO

Setting up physiologically relevant in vitro models requires realizing a proper hierarchical cellular structure, wherein the main tissue features are recapitulated [...].


Assuntos
Materiais Biocompatíveis , Engenharia Tecidual , Materiais Biocompatíveis/química
9.
J Environ Manage ; 345: 118591, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37423188

RESUMO

Global plastic production is rapidly increasing, resulting in significant amounts of plastic entering the marine environment. This makes marine litter one of the most critical environmental concerns. Determining the effects of this waste on marine animals, particularly endangered organisms, and the health of the oceans is now one of the top environmental priorities. This article reviews the sources of plastic production, its entry into the oceans and the food chain, the potential threat to aquatic animals and humans, the challenges of plastic waste in the oceans, the existing laws and regulations in this field, and strategies. Using conceptual models, this study looks at a circular economy framework for energy recovery from ocean plastic wastes. It does this by drawing on debates about AI-based systems for smart management. In the last sections of the present research, a novel soft sensor is designed for the prediction of accumulated ocean plastic waste based on social development features and the application of machine learning computations. Plus, the best scenario of ocean plastic waste management with a concentration on both energy consumption and greenhouse gas emissions is discussed using USEPA-WARM modeling. Finally, a circular economy concept and ocean plastic waste management policies are modeled based on the strategies of different countries. We deal with green chemistry and the replacement of plastics derived from fossil sources.


Assuntos
Plásticos , Gerenciamento de Resíduos , Animais , Humanos , Inteligência Artificial , Oceanos e Mares , Cadeia Alimentar , Reciclagem
10.
Cytometry A ; 101(12): 995-999, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35716116

RESUMO

The importance of personalized/precision medicine for targeted therapies and improved outcomes both in terms of efficacy and safety in health care is by now grounded. We here discuss the current landscape of personalized medicine approaches against SARS-CoV-2. A schematic of the approach is illustrated in the figure in the text.


Assuntos
COVID-19 , Medicina de Precisão , Humanos , SARS-CoV-2
11.
Crit Rev Biotechnol ; 42(5): 668-692, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34645360

RESUMO

Polymers are synonymous with the modern way of living. However, polymers with a large carbon footprint, especially those derived from nonrenewable petrochemical sources, are increasingly perceived as detrimental to the environment and a sustainable future. Polyhydroxyalkanoate (PHA) is a microbial biopolymer and a plausible alternative for renewable sources. However, PHA in its monomeric forms has very limited applications due to its limited flexibility, tensile strength, and moldability. Herein, the life cycle of PHA molecules, from biosynthesis to commercial utilization for diverse applications is discussed. For clarity, the applications of this bioplastic biocomposite material are further segregated into two domains, namely, the industrial sector and the medical sector. The industry sectors reviewed here include food packaging, textiles, agriculture, automotive, and electronics. High-value addition of PHA for a sustainable future can be foreseen in the medical domain. Properties such as biodegradability and biocompatibility make PHA a suitable candidate for decarbonizing biomaterials during tissue repair, organ reconstruction, drug delivery, bone tissue engineering, and chemotherapeutics.


Assuntos
Poli-Hidroxialcanoatos , Materiais Biocompatíveis , Biopolímeros , Embalagem de Alimentos , Engenharia Tecidual
12.
Crit Rev Biotechnol ; 42(8): 1180-1212, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34823433

RESUMO

Neurodegenerative disorders (NDs) are highly prevalent among the aging population. It affects primarily the central nervous system (CNS) but the effects are also observed in the peripheral nervous system. Neural degeneration is a progressive loss of structure and function of neurons, which may ultimately involve cell death. Such patients suffer from debilitating memory loss and altered motor coordination which bring up non-affordable and unavoidable socio-economic burdens. Due to the unavailability of specific therapeutics and diagnostics, the necessity to control or manage NDs raised the demand to investigate and develop efficient alternative approaches. Keeping trends and advancements in view, this report describes both state-of-the-art and challenges in nano-biotechnology-based approaches to manage NDs, toward personalized healthcare management. Sincere efforts are being made to customize nano-theragnostics to control: therapeutic cargo packaging, delivery to the brain, nanomedicine of higher efficacy, deep brain stimulation, implanted stimulation, and managing brain cell functioning. These advancements are useful to design future therapy based on the severity of the patient's neurodegenerative disease. However, we observe a lack of knowledge shared among scientists of a variety of expertise to explore this multi-disciplinary research field for NDs management. Consequently, this review will provide a guideline platform that will be useful in developing novel smart nano-therapies by considering the aspects and advantages of nano-biotechnology to manage NDs in a personalized manner. Nano-biotechnology-based approaches have been proposed as effective and affordable alternatives at the clinical level due to recent advancements in nanotechnology-assisted theragnostics, targeted delivery, higher efficacy, and minimal side effects.


Assuntos
Nanopartículas , Doenças Neurodegenerativas , Idoso , Humanos , Sistemas de Liberação de Medicamentos , Nanomedicina , Nanopartículas/química , Nanotecnologia , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/metabolismo
13.
Cells Tissues Organs ; 211(4): 492-505, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33596574

RESUMO

Research on synthesis, characterization, and understanding of novel properties of nanomaterials has led researchers to exploit their potential applications. When compared to other nanotechnologies described in the literature, electrospinning has received significant interest due to its ability to synthesize novel nanostructures (such as nanofibers, nanorods, nanotubes, etc.) with distinctive properties such as high surface-to-volume ratio, porosity, various morphologies such as fibers, tubes, ribbons, mesoporous and coated structures, and so on. Various materials such as polymers, ceramics, and composites have been fabricated using the electrospinning technique. Among them, polymers, especially block copolymers, are one of the useful and niche systems studied recently owing to their unique and fascinating properties in both solution and solid state due to thermodynamic incompatibility of the blocks, that results in microphase separation. Morphology and mechanical properties of electrospun block copolymers are intensely influenced by quantity and length of soft and hard segments. They are one of the best studied systems to fit numerous applications due to a broad variety of properties they display upon varying the composition ratio and molecular weight of blocks. In this review, the synthesis, fundamentals, electrospinning, and tissue engineering application of block copolymers are highlighted.


Assuntos
Nanofibras , Engenharia Tecidual , Nanofibras/química , Nanotecnologia , Polímeros/química , Porosidade , Engenharia Tecidual/métodos
14.
Nanotechnology ; 33(32)2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34252888

RESUMO

Photothermal anti-icing/deicing technology is an environmentally friendly surface technology that can be applied to the surface of aircraft, vehicles or ships. However, it is still a huge challenge to develop a strong and stable flexible film that can efficiently convert light to heat. Here, based on a simple electrochemical method to construct a zinc oxide (ZnO) nanoneedles structure on the surface of the carbon nanotube film, a film with the function of condensed micro-droplet self-propelling (CMDSP) was successfully prepared. The prepared film has excellent light absorption capacity and high energy transfer efficiency (76.71%). The film has strong photothermal anti-icing/deicing performance. Under 4406 Lux light irradiation, even under low temperature conditions of -5 °C, the icing delay time exceeds 4 h. This novel characteristic is attributed to the CMDSP function on the surface and the ultra-fast evaporation mechanism, which can remove water droplets on the surface as quickly as possible. This function helps to design energy-saving equipment that requires high-power heating and deicing.

15.
Environ Res ; 213: 113631, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35714685

RESUMO

Blockchain-integrated waste management and circular economy are emergent concepts that target minimising waste generation and fluctuations of resource commodity. Blockchain can support a circular economy and green principles by enabling information transparency, reliability and automation. Redesigning plastics by molecular tagging is the way forward to ensure synthetic plastics are kept in an infinite loop and support closed-loop recycling. The involvement of major corporations in product development and blockchain-integrated closed-loop recycling has resulted in several successful green chemical approaches toward circular plastic economy projects. Government policies and legislations are progressively supporting plastic redesigning for improving the plastic circular economy. Nevertheless, a systematic approach is required in addressing blockchain technology and plastic redesigning to effectively leverage circular economy initiatives.


Assuntos
Blockchain , Gerenciamento de Resíduos , Plásticos , Reciclagem , Reprodutibilidade dos Testes
16.
JOM (1989) ; 74(9): 3392-3407, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35228788

RESUMO

Herbal drugs are safe and show significantly fewer side effects than their synthetic counterparts. Curcumin (an active ingredient primarily found in turmeric) shows therapeutic properties, but its commercial use as a medication is unrealized, because of doubts about its potency. The literature reveals that electrospun nanofibers show simplicity, efficiency, cost, and reproducibility compared to other fabricating techniques. Forcespinning is a new technique that minimizes limitations and provides additional advantages to electrospinning. Polymer-based nanofibers-whose advantages lie in stability, solubility, and drug storage-overcome problems related to drug delivery, like instability and hydrophobicity. Curcumin-loaded polymer nanofibers show potency in healing diabetic wounds in vitro and in vivo. The release profiles, cell viability, and proliferation assays substantiate their efficacy in bone tissue repair and drug delivery against lung, breast, colorectal, squamous, glioma, and endometrial cancer cells. This review mainly discusses how polymer nanofibers interact with curcumin and its medical efficacy.

17.
Drug Metab Rev ; 53(1): 141-170, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33138652

RESUMO

The global spread of the novel coronavirus (SARS-CoV-2) and increasing rate of mortality among different countries has raised the global concern regarding this disease. This illness is able to infect human beings through person-to-person contact at an extremely high rate. World Health Organization proclaimed that COVID-19 disease is known as the sixth public health emergency of international concern (30 January 2020) and also as one pandemic (12 March 2020). Owing to the rapid outbreak of COVID-19 worldwide, health authorities focused on discovery of effective prevention and treatment techniques for this novel virus. To date, an effective drug for reliable treatment of COVID-19 has not been registered or introduced to the international community. This review aims to provide recently presented techniques and protocols for efficient treatment of COVID-19 and investigate its morphology and treatment/prevention approaches, among which usage of antiviral drugs, anti-malarial drugs, corticosteroids, and traditional medicines, biotechnological drugs (e.g. combination of HCQ and azithromycin, remdesivir, interferons, novaferon, interferon-alpha-1b, thymosin, and monoclonal antibodies) can be mentioned.


Assuntos
Antivirais , Tratamento Farmacológico da COVID-19 , Antivirais/classificação , Antivirais/farmacologia , Quimioterapia Combinada/métodos , Humanos , Conduta do Tratamento Medicamentoso , SARS-CoV-2
18.
Mater Sci Eng R Rep ; 143: 100594, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33519094

RESUMO

The outbreak of Coronavirus Disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has triggered great global public health concern. Face masks are essential tools to reduce the spread of SARS-CoV-2 from human to human. However, there are still challenges to prolong the serving life and maintain the filtering performance of the current commercial mask. Filters composed of ultrafine fibers with diameter down to tens of nanometers have the potential to physically block viruses. With adjustable composition and nanostructures, the electrospun ultrafine fiber filter is possible to achieve other necessary functions beyond virus blocking, such as antiviral, transparent, and degradable, making it an important part of fighting the epidemic. In this review, beginning with the basic information of the viruses, we summarize the knowledge of masks and respirators, including the filtering mechanism, structure, classification, and standards. We further present the fabrication method, filtering performance, and reusable potential of electrospun ultrafine fiber-based masks. In the end, we discuss the development directions of ultrafine fibers in protective devices, especially their new functional applications and possible contributions in the prevention and control of the epidemic.

19.
Opt Lett ; 46(15): 3801-3804, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34329285

RESUMO

A method to realize surface-enhanced Raman spectroscopy (SERS) at a titanium alloy substrate for glucose detection has been experimentally demonstrated. A silver-coated laser-induced periodic surface structure (LIPSS) was prepared via femtosecond laser micro-processing. The low detection limit of glucose is 10-7mol/L and, a good linear relationship between the glucose concentration and Raman intensity is found in the range between 1×10-7 and 1×10-3mol/L. Moreover, we investigate SERS detection for glucose sensing in human urine samples, while the results are in good agreement with clinical results. The Letter provides a facile method for producing a structure-controlled SERS substrate to realize glucose detection, which is promising for long-term in vivo diagnostics.


Assuntos
Diabetes Mellitus , Nanopartículas Metálicas , Diabetes Mellitus/diagnóstico , Humanos , Limite de Detecção , Prata , Análise Espectral Raman , Titânio
20.
Chem Rec ; 21(5): 1098-1118, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33913239

RESUMO

Providing energy and materials are considered one most important issue in the world. Produce and storage energy and also, prepare chemical substances from disposable biomass materials have been widely developed in recent decades to decrease environmental pollutions and production costs. The waste of hot drinks including coffee wastes and tea wastes have considerable potentials to provide energy and different chemical substances. Also, hazardous materials (especially aqueous ions) can be absorbed via hot drinks wastes to protect the environment against perilous pollutants. The low-cost and benign hot drinks wastes including tea wastes and coffee grounds and also the pyrolyzed of them as the hot drinks waste biochar materials have been widely used to produce and store green energies and also, absorb hazardous materials. Production and storage energy and environmental remediation in these sustainable procedures not only reduce the cost of energy but also protect the environment.


Assuntos
Coffea/química , Recuperação e Remediação Ambiental , Energia Renovável , Chá/química , Resíduos
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