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1.
Food Chem ; 398: 133761, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35961167

RESUMO

In this study, yolk-shell Fe3O4-based nanomaterials designing of fluorescent aptasensor using a new type of biomimetic network-constitutional dynamic networks (CDNs) amplification strategy was developed for aflatoxin B1 (AFB1) detection. By ingeniously designing the base sequences A, a, B, b, and coupling with endonuclease (BbvCI), a constitutes of CDNs is formed as a fluorescence intensity amplifier. With such design, the as- prepared aptasensor exhibits good sensitivity from 50 fg·mL-1-50 ng·mL-1 with a detection limit of 35.94 fg·mL-1. Moreover, the CDNs can achieve 1000-fold amplification in terms of linear range and detection limit. The results confirmed that this new type of biomimetic network amplification strategy can supply-one efficient approach to improve signal amplification. Furthermore, the prepared aptamer sensor was tested for spiked recovery in peanut samples, and the recoveries ranged from 83.79 to 95.06 %, which has confirmed its practical application value in the field of food safety.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Nanopartículas Metálicas , Nanoestruturas , Aflatoxina B1/análise , Biomimética , Técnicas Biossensoriais/métodos , Limite de Detecção
2.
Food Chem ; 398: 133798, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35964570

RESUMO

Amyloid-based nanostructures from food sources have been received intensive interests recently in material science, biomedicine and especially delivery system. This is due to the ability of protein-based amyloid architecture that proved to be an attractive system to carry drug and nutrition. However, few research focused on the modification of functional properties of different fractions isolated from amyloid fibrils. Hereby, we separated the retentate (RGFs) and filtrate (FGFs) fractions from rice glutelin fibrils (GFs) using centrifugal filtration and then investigated the structural characteristics and functional properties of these fractions. We proved that protein fibrillization would highly improve both emulsifying and antioxidant abilities of protein dispersion. In addition, further processed RGFs with rich ß-sheet structures exhibited a similar functional performance to GFs dispersion. By contrast, FGFs dispersion with less ß- sheet content, lower molecular weight, interestingly re-assembled into spherical aggregates with weaker interaction, exhibiting better antioxidant and emulsifying properties.


Assuntos
Nanoestruturas , Oryza , Amiloide/química , Antioxidantes/química , Glutens/química , Nanoestruturas/química , Oryza/química
3.
Opt Lett ; 47(18): 4814-4817, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36107097

RESUMO

Optical chirality plays a key role in optical biosensing and spin-selective optical field manipulation. However, the maximum optical intrinsic chirality, which is represented by near-unity circular dichroism (CD), is yet to be achieved in a wide bandwidth range based on nanostructures. Here, we utilize dielectric bilayer polyatomic metasurfaces to realize the maximum optical intrinsic chirality over a wide bandwidth range. The CD efficiency of the two designed metasurfaces with opposite chirality is 99.9% at 1350 nm and over 98% from 1340 nm to 1361 nm. Our work provides a straightforward and powerful method for the realization of maximum optical intrinsic chirality, which has great potential in spin-selective optical wave manipulation.


Assuntos
Nanoestruturas , Dicroísmo Circular
4.
PLoS One ; 17(9): e0274753, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36112659

RESUMO

Nowadays, fungal infections increase, and the demand of novel antifungal agents is constantly rising. In the present study, silver, titanium dioxide, cobalt (II) hydroxide and cobalt (II,III) oxide nanomaterials have been synthesized from Spirulina platensis extract. The synthesis mechanism has been studied using GCMS and FTIR thus confirming the involvement of secondary metabolites, mainly amines. The obtained products have been analysed using XRD, SEM, TGA and zeta potential techniques. The findings revealed average crystallite size of 15.22 nm with 9.72 nm for oval-shaped silver nanoparticles increasing to 26.01 nm and 24.86 nm after calcination and 4.81 nm for spherical-shaped titanium dioxide nanoparticles which decreased to 4.62 nm after calcination. Nanoflake shape has been observed for cobalt hydroxide nanomaterials and for cobalt (II, III) oxide with crystallite size of 3.52 nm and 13.28 nm, respectively. Silver nanoparticles showed the best thermal and water dispersion stability of all the prepared structures. Once subjected to three different Candida species (C. albicans, C. glabrata, and C. krusei) silver nanoparticles and cobalt (II) hydroxide nanomaterials showed strong antifungal activity at 50 µg/mL with minimum inhibitory concentration (MIC) values. After light exposition, MIC values for nanomaterials decreased (to 12.5 µg/mL) for C. krusei and increased (100 µg/mL) for C. albicans and C. glabrata.


Assuntos
Nanopartículas Metálicas , Nanoestruturas , Aminas , Antifúngicos/química , Antifúngicos/farmacologia , Candida albicans , Candida glabrata , Cobalto , Nanopartículas Metálicas/química , Óxidos , Extratos Vegetais/farmacologia , Prata/química , Spirulina , Titânio , Água
5.
Transl Vis Sci Technol ; 11(9): 1, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36048013

RESUMO

Purpose: The purpose of this study was to improve the biomechanical properties of the cornea through the incorporation of carbon nanostructures. Methods: Healthy Japanese rabbits were used to evaluate the effect of carbon nanostructures' incorporation in the cornea. Rabbits were divided in two groups A and B. In each of these groups, the corneas were divided in (i) corneas not submitted to any treatment (the control group), (ii) corneas modified either with carbon nanostructures (group A), or with the traditional cross-linking technology (group B). After modification, rabbits were euthanized at different time intervals. The biomechanical properties of the treated corneas were evaluated using the inflation method. Results: Biomechanical tests based on the inflation method show that the incorporation of carbon nanostructures to the cornea and their proper distribution within it gives rise to a large improvement in the mechanical properties and tangential elastic modulus (up to 155%). These results anticipate that this novel and easy approach based on nanotechnology is able to compete with the actual cross-linking technology applied in clinical ophthalmology using a photosensitive molecule, such as riboflavin and unpleasant UV-A radiation. Conclusions: The incorporation of carbon nanostructures (single-walled carbon nanotubes and graphene) in corneal stroma is proposed as a promising alternative to improve the mechanical properties in the treated eyes. The proper dispersion of the carbon nanostructures a few days after implementation (down to 60 micrometers depth) explains the successful results achieved. Translational Relevance: Nanotechnology applied to the eye constitutes a promising approach for ocular tissue reinforcement.


Assuntos
Nanoestruturas , Nanotubos de Carbono , Animais , Fenômenos Biomecânicos , Reagentes de Ligações Cruzadas , Fármacos Fotossensibilizantes/uso terapêutico , Coelhos
6.
Drug Deliv ; 29(1): 2912-2924, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36081335

RESUMO

Vaccinations, especially DNA vaccines that promote host immunity, are the most effective interventions for tuberculosis (TB) control. However, the vaccine delivery system exhibits a significant impact on the protective effects of the vaccine. Recently, effective nanomaterial-based delivery systems (including nanoparticles, nanogold, nanoliposomes, virus-like particles, and virus carriers) have been developed for DNA vaccines to control TB. This review highlights the historical development of various nanomaterial-based delivery systems for TB DNA vaccines, along with the emerging technologies. Nanomaterial-based vaccine delivery systems could enhance the efficacy of TB vaccination; therefore, this summary could guide nanomaterial selection for optimal and safe vaccine delivery, facilitating the design and development of highly effective TB vaccines.


Assuntos
Mycobacterium tuberculosis , Nanoestruturas , Vacinas contra a Tuberculose , Tuberculose , Vacinas de DNA , DNA , Humanos , Tuberculose/prevenção & controle , Vacinação
7.
ACS Appl Mater Interfaces ; 14(36): 41640-41648, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36047566

RESUMO

The nanostructuration of biolayers has become a paradigm for exploiting nanoscopic light-matter phenomena for biosensing, among other biomedical purposes. In this work, we present a photopatterning method to create periodic structures of biomacromolecules based on a local and periodic mild denaturation of protein biolayers mediated by UV-laser irradiation. These nanostructures are constituted by a periodic modulation of the protein activity, so they are free of topographic and compositional changes along the pattern. Herein, we introduce the approach, explore the patterning parameters, characterize the resulting structures, and assess their overall homogeneity. This UV-based patterning principle has proven to be an easy, cost-effective, and fast way to fabricate large areas of homogeneous one-dimensional protein patterns (2 min, 15 × 1.2 mm, relative standard deviation ≃ 16%). This work also investigates the implementation of these protein patterns as transducers for diffractive biosensing. Using a model immunoassay, these patterns have demonstrated negligible signal contributions from non-specific bindings and comparable experimental limits of detection in buffer media and in human serum (53 and 36 ng·mL-1 of unlabeled IgG, respectively).


Assuntos
Técnicas Biossensoriais , Nanoestruturas , Fenômenos Biofísicos , Humanos , Imunoensaio/métodos , Lasers , Nanoestruturas/química , Transdutores
8.
Front Immunol ; 13: 979469, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36072591

RESUMO

Cancer represents the leading global driver of death and is recognized as a critical obstacle to increasing life expectancy. In recent years, with the development of precision medicine, significant progress has been made in cancer treatment. Among them, various therapies developed with the help of the immune system have succeeded in clinical treatment, recognizing and killing cancer cells by stimulating or enhancing the body's intrinsic immune system. However, low response rates and serious adverse effects, among others, have limited the use of immunotherapy. It also poses problems such as drug resistance and hyper-progression. Fortunately, thanks to the rapid development of nanotechnology, engineered multifunctional nanomaterials and biomaterials have brought breakthroughs in cancer immunotherapy. Unlike conventional cancer immunotherapy, nanomaterials can be rationally designed to trigger specific tumor-killing effects. Simultaneously, improved infiltration of immune cells into metastatic lesions enhances the efficiency of antigen submission and induces a sustained immune reaction. Such a strategy directly reverses the immunological condition of the primary tumor, arrests metastasis and inhibits tumor recurrence through postoperative immunotherapy. This paper discusses several types of nanoscale biomaterials for cancer immunotherapy, and they activate the immune system through material-specific advantages to provide novel therapeutic strategies. In summary, this article will review the latest advances in tumor immunotherapy based on self-assembled, mesoporous, cell membrane modified, metallic, and hydrogel nanomaterials to explore diverse tumor therapies.


Assuntos
Nanoestruturas , Neoplasias , Materiais Biocompatíveis , Humanos , Sistema Imunitário/patologia , Imunoterapia
9.
Nanotheranostics ; 6(4): 400-423, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36051855

RESUMO

Over the last few years, progress has been made across the nanomedicine landscape, in particular, the invention of contemporary nanostructures for cancer diagnosis and overcoming complexities in the clinical treatment of cancerous tissues. Thanks to their small diameter and large surface-to-volume proportions, nanomaterials have special physicochemical properties that empower them to bind, absorb and transport high-efficiency substances, such as small molecular drugs, DNA, proteins, RNAs, and probes. They also have excellent durability, high carrier potential, the ability to integrate both hydrophobic and hydrophilic compounds, and compatibility with various transport routes, making them especially appealing over a wide range of oncology fields. This is also due to their configurable scale, structure, and surface properties. This review paper discusses how nanostructures can function as therapeutic vectors to enhance the therapeutic value of molecules; how nanomaterials can be used as medicinal products in gene therapy, photodynamics, and thermal treatment; and finally, the application of nanomaterials in the form of molecular imaging agents to diagnose and map tumor growth.


Assuntos
Nanoestruturas , Neoplasias , Humanos , Oncologia , Nanomedicina , Nanoestruturas/química , Nanoestruturas/uso terapêutico , Nanotecnologia , Neoplasias/diagnóstico , Neoplasias/terapia
10.
Int J Mol Sci ; 23(17)2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36077397

RESUMO

In this paper, density functional theory (DFT) was used to study the possibility of low-dimensional (2D, 1D, 0D) boron nitride nanomaterials to catalyze acetylene acetate reaction, and further explore the possible source of this catalytic activity. It is found that the catalytic activity of boron nitride nanomaterials for acetylene acetate reaction will change with the change of the geometric structure (dimension) and reaction site of the catalyst. From the geometric structure, the reaction components and the zero-dimensional BN catalyst can form chemical bonds and form complexes, while only physical adsorption occurs on the surface of the one-dimensional and two-dimensional BN catalysts. From the reaction site, the properties of different C sites on the B12N12NC-C2H2 complexes are different. Namely, a C atom connected with a B atom is more likely to have an electrophilic reaction with H+, and a C atom connected with an N atom is more likely to have a nucleophilic reaction with CH3COO-. Through the study of three kinds of BN nanomaterials with low dimensions, we found that the zero-dimensional B12N12 nanocage broke the inherent reaction inertia of BN materials and showed good catalytic activity in an acetylene acetate reaction, which is very likely to be a non-metallic catalyst for the acetylene gas-phase preparation of vinyl acetate.


Assuntos
Acetileno , Nanoestruturas , Acetatos , Acetileno/química , Compostos de Boro , Teoria da Densidade Funcional , Nanoestruturas/química
11.
Molecules ; 27(17)2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36080194

RESUMO

Nanozymes are nanomaterials with intrinsic natural enzyme-like catalytic properties. They have received extensive attention and have the potential to be an alternative to natural enzymes. Increasing the atom utilization rate of active centers in nanozymes has gradually become a concern of scientists. As the limit of designing nanozymes at the atomic level, single-atom nanozymes (SAzymes) have become the research frontier of the biomedical field recently because of their high atom utilization, well-defined active centers, and good natural enzyme mimicry. In this review, we first introduce the preparation of SAzymes through pyrolysis and defect engineering with regulated activity, then the characterization and surface modification methods of SAzymes are introduced. The possible influences of surface modification on the activity of SAzymes are discussed. Furthermore, we summarize the applications of SAzymes in the biomedical fields, especially in those of reactive oxygen species (ROS) scavenging and antibacterial. Finally, the challenges and opportunities of SAzymes are summarized and prospected.


Assuntos
Nanoestruturas , Antibacterianos/farmacologia , Biomimética , Catálise , Espécies Reativas de Oxigênio
12.
Molecules ; 27(17)2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36080349

RESUMO

Hydroxyapatite (HA) is a well-known calcium phosphate ingredient comparable to human bone tissue. HA has exciting applications in many fields, especially biomedical applications, such as drug delivery, osteogenesis, and dental implants. Unfortunately, hydroxyapatite-based nanomaterials are synthesized by conventional methods using reagents that are not environmentally friendly and are expensive. Therefore, extensive efforts have been made to establish a simple, efficient, and green method to form nano-hydroxyapatite (NHA) biofunctional materials with significant biocompatibility, bioactivity, and mechanical strength. Several types of biowaste have proven to be a source of calcium in forming HA, including using chicken eggshells, fish bones, and beef bones. This systematic literature review discusses the possibility of replacing synthetic chemical reagents, synthetic pathways, and toxic capping agents with a green template to synthesize NHA. This review also shed insight on the simple green manufacture of NHA with controlled shape and size.


Assuntos
Durapatita , Nanoestruturas , Animais , Osso e Ossos , Bovinos , Sistemas de Liberação de Medicamentos , Humanos , Osteogênese
13.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 613-616, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36086108

RESUMO

Metallic nanostructured-based biosensors provide label-free, multiplexed, and real-time detections of chemical and biological targets. Aluminum-based biosensors are favored in this category, due to their enhanced stability and profitability. Despite the recent advances in nanotechnology and the significant improvement in development of these biosensors, some deficiencies restrict their utilization. Hence a detailed insight into their behavior in different conditions would be crucial, which can be achieved with nanoscale numerical simulation. With this aim, an Aluminum-based biosensor is chosen to be analyzed with the help of all-atom molecular dynamics model (AA-MD), using large-scale atomic/molecular massively parallel simulator (LAMMPS). The surface properties and adsorption process through different flow conditions and various concentration of the target, are investigated in this study. In the future work, the results of this study will be used for developing a predictive model for surface properties of the biosensor. Clinical Relevance- The role of biosensors in clinical applications and early diagnosis is evident. This work provides a model for predicting the binding behavior of the target molecules on the biosensor surface in different conditions. Results demonstrate an increase in the adsorption of ethanol on the biosensor surface of 7% up to 80% with changing the velocity from 0.001 m/s to 1 m/s Although for cases with higher concentration this trend becomes complicated necessitating the implementation of machine learning models in the future works.


Assuntos
Técnicas Biossensoriais , Nanoestruturas , Alumínio , Técnicas Biossensoriais/métodos , Simulação de Dinâmica Molecular , Nanoestruturas/química , Nanotecnologia
14.
Environ Monit Assess ; 194(10): 730, 2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-36066693

RESUMO

Nanomaterials (NMs) are currently being used in agricultural soils as part of a new bioremediation (BR) process. In this study, we reviewed the biosynthesis of NMs, as well as their chemical composition and prospective strategies for helpful and sustainable agricultural soil bioremediation (BR). Different types of NMs, such as nanoparticles, nanocomposites, nanocrystals, nano-powders, and nanotubes, are used in agricultural soil reclamation, and they reflect the toxicity of NMs to microorganisms. Plants (Sargassum muticum, Dodonaea viscose, Aloe Vera, Rosemarinus officinalis, Azadirachta indica, Green tea, and so on) and microorganisms (Escherichia coli, Shewanella oneidensis, Pleurotus sp., Klebsiella oxytoca, Aspergillus clavatus, and so on) are the primary sources for the biosynthesis of NMs. By using the BR process, microorganisms, such as bacteria and plants, can immobilize metals and change both inorganic and organic contaminants in the soil. Combining NMs with bioremediation techniques for agricultural soil remediation will be a valuable long-term solution.


Assuntos
Nanoestruturas , Poluentes do Solo , Biodegradação Ambiental , Monitoramento Ambiental , Plantas , Estudos Prospectivos , Solo/química , Poluentes do Solo/análise
15.
Biosens Bioelectron ; 216: 114662, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36058027

RESUMO

Nanozymes, an emerging family of heterogeneous nanomaterials with enzyme-like characteristics, offer significant advantages as alternatives to natural enzymes for diverse biocatalytic applications. Nevertheless, the inhomogeneous configuration of nanomaterials makes it extremely challenging to develop nanozymes of desired performance and reaction mechanism. Single-atom nanozymes (SAzymes) that are composed of single-atomic active sites may provide an answer to these challenges with remarkable enzyme-like activity and specificity. The well-defined coordination microenvironments of SAzymes offer a suitable model system to investigate the structure-activity relationship and thus bridge the gap between natural enzyme and nanozyme. In this review, we would first present an overview of discoveries, advantages, and classifications of SAzymes. Then, we would discuss the reaction mechanism, design principles, and biosensing applications of a series of typical SAzymes with a focus on the rational design strategies for targeted reaction and the effort to uncover the catalytic mechanism at the atomic scale. Finally, we would provide the challenges and future perspectives of SAzymes as the next-generation nanozymes.


Assuntos
Técnicas Biossensoriais , Nanoestruturas , Catálise , Domínio Catalítico , Nanoestruturas/química
16.
Nanoscale ; 14(36): 13292-13307, 2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-36063033

RESUMO

Upon coming into contact with the biological environment, nanostructures are immediately covered by biomolecules, particularly by proteins forming the so-called "protein corona" (PC). The phenomenon of PC formation has gained great attention in recent years due to its implication in the use of nanostructures in biomedicine. In fact, it has been shown that the formation of the PC can impact the performance of nanostructures by reducing their stability, causing aggregation, increasing their toxicity, and providing unexpected and undesired nanostructure-cell interactions. In this work, we decided to study for the first time the formation and the evolution of PC on the surface of nanostructured lipid carriers loaded with superparamagnetic iron oxide nanoparticles, before and after the crossing of an in vitro model of the blood-brain barrier (BBB). Combining confocal microscopy, direct STochastic Optical Reconstruction Microscopy (dSTORM), and proteomic analysis, we were able to carry out a complete analysis of the PC formation and evolution. In particular, we highlighted that PC formation is a fast process, being formed around particles even after just 1 min of exposure to fetal bovine serum. Moreover, PC formed around particles is extremely heterogeneous: while some particles have no associated PC at all, others are completely covered by proteins. Lastly, the interaction with an in vitro BBB model strongly affects the PC composition: in particular, a large amount of the proteins forming the initial PC is lost after the BBB passage and they are partially replaced by new proteins derived from both the brain endothelial cells and the cell culture medium. Altogether, the obtained data could potentially provide new insights into the design and fabrication of lipid nanostructures for the treatment of central nervous system disorders.


Assuntos
Nanopartículas , Nanoestruturas , Coroa de Proteína , Barreira Hematoencefálica/metabolismo , Células Endoteliais/metabolismo , Lipídeos , Espectrometria de Massas , Microscopia Confocal , Nanopartículas/química , Coroa de Proteína/química , Proteômica , Soroalbumina Bovina/metabolismo
17.
Anal Chem ; 94(37): 12866-12874, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36069149

RESUMO

Developing rapid detection technology for adenosine triphosphate (ATP) is crucial in quality supervision and food safety. Herein, an electrochemical aptasensor based on an aptazyme-catalyzed signal amplification strategy is constructed for ATP detection using polyethyleneimine-functionalized molybdenum disulfide (PEI-MoS2)/Au@PtPd nanobipyramids (MoS2/Au@PtPd NBPs) as a modification material. Additionally, a novel kind of nitrogen-rich covalent organic framework (COF) is prepared using melamine and cyanuric acid (MCA). We synthesize MCA and the Co-based metal organic framework (Co-MOF) as the signal label. Due to the fact that π-π stacking interactions of Co-MOF@MCA can expand the load efficiency and surface concentration of the signal label, the signal response is an order of magnitude higher than that of Co-MOF or MCA as the signal label. Target ATP changes the conformation of the aptazyme, and it becomes activated. With the assistance of metal ions, the signal label is circularly cleaved, causing an amplification of the signal. Among them, MoS2/Au@PtPd NBPs have a large specific surface area and good electrical conductivity and can carry substantial DNA strands and amplify the redox signal of methylene blue (MB). Under optimal conditions, the aptasensor can detect ATP from 10 pM to 100 µM with a low limit of detection of 7.37 × 10-10 µM. Therefore, the novel aptasensor has extensive application prospects in quality supervision and food safety.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Nanopartículas Metálicas , Estruturas Metalorgânicas , Nanoestruturas , Trifosfato de Adenosina , Aptâmeros de Nucleotídeos/química , Técnicas Eletroquímicas , Ouro/química , Limite de Detecção , Nanopartículas Metálicas/química , Estruturas Metalorgânicas/química , Azul de Metileno , Molibdênio/química , Nanoestruturas/química , Nitrogênio , Polietilenoimina , Triazinas
18.
Langmuir ; 38(37): 11137-11148, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36070512

RESUMO

Understanding the behaviors of nanoparticles at interfaces is crucial not only for the design of novel nanostructured materials with superior properties but also for a better understanding of many biological systems where nanoscale objects such as drug molecules, viruses, and proteins can interact with various interfaces. Theoretical studies and tailored computer simulations offer unique approaches to investigating the evolution and formation of structures as well as to determining structure-property relationships regarding the interfacial nanostructures. In this feature article, we summarize our efforts to exploit computational approaches as well as theoretical modeling in understanding the organization of nanoscale objects at the interfaces of various systems. First, we present the latest research advances and state-of-the-art computational techniques for the simulation of nanoparticles at interfaces. Then we introduce the applications of multiscale modeling and simulation methods as well as theoretical analysis to explore the basic science and the fundamental principles in the interfacial nanoparticle organization, covering the interfaces of polymer, nanoscience, biomacromolecules, and biomembranes. Finally, we discuss future directions to signify the framework in tailoring the interfacial organization of nanoparticles based on the computational design. This feature article could promote further efforts toward fundamental research and the wide applications of theoretical approaches in designing interfacial assemblies for new types of functional nanomaterials and beyond.


Assuntos
Nanopartículas , Nanoestruturas , Simulação por Computador , Modelos Teóricos , Nanopartículas/química , Nanoestruturas/química , Polímeros/química
19.
Phys Chem Chem Phys ; 24(36): 22122-22128, 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36074749

RESUMO

On-surface synthesis has been a subject of intensive research during the last decade. Various chemical reactions have been developed on surfaces to prepare compounds and carbon nanostructures, most of which are centered on the carbon-carbon bond formation. Despite the vast progress so far, the diversity of functional groups in organic chemistry has been far less explored in on-surface synthesis. Herein, we study the surface-assisted synthesis of ethers through the homocoupling of hydroxymethyl substituents on Ag(111). By using two hydroxymethyl substituent functionalized molecular precursors with different symmetries, we have achieved the formation of ether chains and rings. High-resolution scanning tunneling microscopy complemented with density functional theory calculations are used to support our findings and offer mechanistic insights into the reaction. This work expands the toolbox of on-surface reactions for the bottom-up fabrication of more sophisticated functional nanostructures.


Assuntos
Éteres , Nanoestruturas , Carbono , Éter , Microscopia de Tunelamento , Nanoestruturas/química
20.
Food Res Int ; 160: 111680, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36076447

RESUMO

Bacterial infection has become an important factor affecting human health, and the increasing antibiotic resistance has seriously hindered the treatment of infectious diseases. This study aimed to explore a novel nanotechnology that combines silver with glutathione (GSH) to form antibacterial nanoclusters, GSH@AgNCs. The composite was characterized using a UV fluorescence spectrophotometer, high-resolution transmission electron microscopy (HR-TEM), particle size-zeta potential, fourier transform infrared (FTIR), X-ray photoelectron spectrometer (XPS), thermal gravimetric analysis (TGA), and X-ray diffraction analysis (XRD). This study examined the inhibitory effect of GSH@AgNCs on the bacterial growth and biofilm formation of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), as well as its antibacterial mechanisms. The results indicated that GSH@AgNCs were more successful in restricting E. coli than S. aureus. The bacterial membrane exposed to GSH@AgNCs was damaged irreversibly, presenting cytoplasm leakage, membrane depolarization, ATPase activity decline, and cell degeneration. In addition, at low concentration (1/8 MIC), GSH@AgNCs significantly inhibited the formation of biofilms and damaged mature biofilms, reducing the viable cells. This study demonstrated that GSH@AgNCs effectively hindered the proliferation of foodborne Gram-positive bacteria (S. aureus) and Gram-negative bacteria (E. coli), providing new feasibility for applying organic composite nanomaterials and nanotechnology in the food industry.


Assuntos
Infecções por Escherichia coli , Prata , Antibacterianos/farmacologia , Biofilmes , Escherichia coli , Glutationa , Humanos , Nanoestruturas , Prata/farmacologia , Staphylococcus aureus
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