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1.
Nat Commun ; 15(1): 3015, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589344

RESUMO

Many experimental and computational efforts have sought to understand DNA origami folding, but the time and length scales of this process pose significant challenges. Here, we present a mesoscopic model that uses a switchable force field to capture the behavior of single- and double-stranded DNA motifs and transitions between them, allowing us to simulate the folding of DNA origami up to several kilobases in size. Brownian dynamics simulations of small structures reveal a hierarchical folding process involving zipping into a partially folded precursor followed by crystallization into the final structure. We elucidate the effects of various design choices on folding order and kinetics. Larger structures are found to exhibit heterogeneous staple incorporation kinetics and frequent trapping in metastable states, as opposed to more accessible structures which exhibit first-order kinetics and virtually defect-free folding. This model opens an avenue to better understand and design DNA nanostructures for improved yield and folding performance.


Assuntos
Nanoestruturas , Nanotecnologia , Conformação de Ácido Nucleico , DNA/química , Nanoestruturas/química , Cinética
2.
Biosens Bioelectron ; 255: 116238, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38579625

RESUMO

Efficient real-time diagnostics and on-demand drug delivery are essential components in modern healthcare, especially for managing chronic diseases. The lack of a rapid and effective sensing and therapeutic system can result in analyte level deviations, leading to severe complications. Minimally invasive microneedle (MN)-based patches integrating nanostructures (NSs) in their volume or on their surface have emerged as a biocompatible technology for delay-free analyte sensing and therapy. However, a quantitative relationship for the signal response in NS-assisted reactions remains elusive. Existing generalized formalisms are derived for in-vitro applications, raising questions about their direct applicability to in-situ wearable sensors. In this study, we apply the reaction-diffusion theory to establish a generalized physics-guided framework for NS-in-MN platforms in wearable applications. The model relates the signal response to analyte concentration, incorporating geometric, physical, and catalytic platform properties. Approximating the model under NS (binding or catalytic) and environmental (mass transport) limitations, we validate it against numerical simulations and various experimental results from diverse conditions - analyte sensing (glucose, lactic acid, pyocyanin, miRNA, etc.) in artificial and in-vivo environments (humans, mice, pigs, plants, etc.) through electrochemical and optical/colorimetric, enzymatic and non-enzymatic platforms. The results plotted in the scaled response show that (a) NS-limited platforms exhibit a linear dependence, (b) Mass transport-limited platforms saturate to 1, (c) a one-to-one mapping against traditional sensitivity plots unifies the scattered data points reported in literature. The universality of the model provides insightful perspectives for the design and optimization of MN-based sensing technologies, with potential extensions to dissolvable MNs as part of analyte-responsive closed-loop therapeutic applications.


Assuntos
Técnicas Biossensoriais , Nanoestruturas , Humanos , Animais , Suínos , Camundongos , Técnicas Biossensoriais/métodos , Nanoestruturas/química , Sistemas de Liberação de Medicamentos/métodos
3.
Biophys Chem ; 309: 107231, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38569455

RESUMO

Nanodisc technology is increasingly being used in structural, biochemical and biophysical studies of membrane proteins. The computational approaches have revealed many important features of nanodisc assembly, structures and dynamics. Therefore, we reviewed the application of computational approaches, especially molecular modeling and molecular dyncamics (MD) simulations, to characterize nanodiscs, including the structural models, assembly and disassembly, protocols for modeling, structural properties and dynamics, and protein-lipid interactions in nanodiscs. More amazing computational studies about nanodiscs are looked forward to in the future.


Assuntos
Nanoestruturas , Nanoestruturas/química , Bicamadas Lipídicas/química , Proteínas de Membrana/química , Modelos Moleculares
4.
Mikrochim Acta ; 191(5): 282, 2024 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-38652326

RESUMO

A novel dual-mode fluorometric and colorimetric sensing platform is reported for determining glutathione S-transferase (GST) by utilizing polyethyleneimine-capped silver nanoclusters (PEI-AgNCs) and cobalt-manganese oxide nanosheets (CoMn-ONSs) with oxidase-like activity. Abundant active oxygen species (O2•-) can be produced through the CoMn-ONSs interacting with dissolved oxygen. Afterward, the pink oxDPD was generated through the oxidation of colorless N,N-diethyl-p-phenylenediamine (DPD) by O2•-, and two absorption peaks at 510 and 551 nm could be observed. Simultaneously, oxDPD could quench the fluorescence of PEI-AgNCs at 504 nm via the inner filter effect (IFE). However, in the presence of glutathione (GSH), GSH prevents the oxidation of DPD due to the reducibility of GSH, leading to the absorbance decrease at 510 and 551 nm. Furthermore, the fluorescence at 504 nm was restored due to the quenching effect of oxDPD on decreased PEI-AgNCs. Under the catalysis of GST, GSH and1-chloro-2,4-dinitrobenzo (CDNB) conjugate to generate an adduct, initiating the occurrence of the oxidation of the chromogenic substrate DPD, thereby inducing a distinct colorimetric response again and the significant quenching of PEI-AgNCs. The detection limits for GST determination were 0.04 and 0.21 U/L for fluorometric and colorimetric modes, respectively. The sensing platform illustrated reliable applicability in detecting GST in real samples.


Assuntos
Cobalto , Colorimetria , Glutationa Transferase , Compostos de Manganês , Nanopartículas Metálicas , Óxidos , Polietilenoimina , Prata , Polietilenoimina/química , Prata/química , Cobalto/química , Óxidos/química , Compostos de Manganês/química , Nanopartículas Metálicas/química , Colorimetria/métodos , Glutationa Transferase/metabolismo , Glutationa Transferase/química , Limite de Detecção , Oxirredutases/química , Oxirredutases/metabolismo , Humanos , Glutationa/química , Oxirredução , Técnicas Biossensoriais/métodos , Fenilenodiaminas/química , Nanoestruturas/química
5.
Luminescence ; 39(4): e4745, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38644416

RESUMO

This study introduces a novel chemiluminescence (CL) approach utilizing FeS2 nanosheets (NSs) catalyzed luminol-O2 CL reaction for the measurement of three pharmaceuticals, namely venlafaxine hydrochloride (VFX), imipramine hydrochloride (IPM), and cefazolin sodium (CEF). The CL method involved the phenomenon of quenching induced by the pharmaceuticals in the CL reaction. To achieve the most quenching efficacy of the pharmaceuticals in the CL reaction, the concentrations of reactants comprising luminol, NaOH, and FeS2 NSs were optimized accordingly. The calibration curves demonstrated exceptional linearity within the concentration range spanning from 4.00 × 10-7 to 1.00 × 10-3 mol L-1, 1.00 × 10-7 to 1.00 × 10-4 mol L-1, and 4.00 × 10-6 to 2.00 × 10-4 mol L-1 with detection limits (3σ) of 3.54 × 10-7, 1.08 × 10-8, and 2.63 × 10-6 mol L-1 for VFX, IPM, and CEF, respectively. This study synthesized FeS2 NSs using a facile hydrothermal approach, and then the synthesized FeS2 NSs were subjected to a comprehensive characterization using a range of spectroscopic methods. The proposed CL method was effective in measuring the aforementioned pharmaceuticals in pharmaceutical formulations as well as different water samples. The mechanism of the CL system has been elucidated.


Assuntos
Cefazolina , Compostos Ferrosos , Imipramina , Medições Luminescentes , Luminol , Cloridrato de Venlafaxina , Cefazolina/análise , Cefazolina/química , Cloridrato de Venlafaxina/análise , Cloridrato de Venlafaxina/química , Imipramina/análise , Imipramina/química , Medições Luminescentes/métodos , Luminol/química , Nanoestruturas/química , Luminescência
6.
Biosens Bioelectron ; 256: 116276, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38599073

RESUMO

Fat mass and obesity-associated protein (FTO) has gained attention as the first RNA N6-methyladenosine (m6A) modification eraser due to its overexpression being associated with various cancers. In this study, an electrochemiluminescence (ECL) biosensor for the detection of demethylase FTO was developed based on DNAzyme-mediated CRISPR/Cas12a signal cascade amplification system and carboxylated carbon nitride nanosheets/phosphorus-doped nitrogen-vacancy modified carbon nitride nanosheets (C-CN/PCNV) heterojunction as the emitter. The biosensor was constructed by modifying the C-CN/PCNV heterojunction and a ferrocene-tagged probe (ssDNA-Fc) on a glassy carbon electrode. The presence of FTO removes the m6A modification on the catalytic core of DNAzyme, restoring its cleavage activity and generating activator DNA. This activator DNA further activates the trans-cleavage ability of Cas12a, leading to the cleavage of the ssDNA-Fc and the recovery of the ECL signal. The C-CN/PCNV heterojunction prevents electrode passivation and improves the electron-hole recombination, resulting in significantly enhanced ECL signal. The biosensor demonstrates high sensitivity with a low detection limit of 0.63 pM in the range from 1.0 pM to 100 nM. Furthermore, the biosensor was successfully applied to detect FTO in cancer cell lysate and screen FTO inhibitors, showing great potential in early clinical diagnosis and drug discovery.


Assuntos
Dioxigenase FTO Dependente de alfa-Cetoglutarato , Técnicas Biossensoriais , Sistemas CRISPR-Cas , DNA Catalítico , Técnicas Eletroquímicas , Limite de Detecção , Medições Luminescentes , Metalocenos , Dioxigenase FTO Dependente de alfa-Cetoglutarato/química , Dioxigenase FTO Dependente de alfa-Cetoglutarato/metabolismo , Humanos , DNA Catalítico/química , Técnicas Eletroquímicas/métodos , Nitrilas/química , Endodesoxirribonucleases/química , Endodesoxirribonucleases/metabolismo , Proteínas Associadas a CRISPR/química , Adenosina/análogos & derivados , Adenosina/análise , Adenosina/química , Nanoestruturas/química , Compostos Ferrosos/química , Proteínas de Bactérias/química , Proteínas de Bactérias/genética
7.
Anal Methods ; 16(16): 2424-2443, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38592715

RESUMO

This review summarizes recent developments in amperometric biosensors, based on one-step electrodeposited organic-inorganic hybrid layers, used for analysis of low molecular weight compounds. The factors affecting self-assembly of one-step electrodeposited films, methods for verifying their composition, advantages, limitations and approaches affecting the electroanalytical performance of amperometric biosensors based on organic-inorganic hybrid layers were systemized. Moreover, issues related to the formation of one-step organic-inorganic hybrid functional layers with different structures in biosensors produced under the same electrodeposition parameters are discussed. The systemized dependencies can support the preliminary choice of functional sensing layers with architectures tuned for specific biotechnology and life science applications. Finally, the capabilities of one-step electrodeposition of organic-inorganic hybrid functional films beyond amperometric biosensors were highlighted.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/instrumentação , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/instrumentação , Galvanoplastia/métodos , Nanoestruturas/química , Eletrodos
8.
Chem Commun (Camb) ; 60(35): 4715-4718, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38596907

RESUMO

Chemically conjugated branched DNA was successfully synthesized by a copper-free click reaction to construct sophisticated and higher-order polyhedral DNA nanostructures with pre-defined units in one pot, which can be used as an efficient nanoplatform to precisely organize multiple gold nanoparticles in predesigned patterns.


Assuntos
DNA , Ouro , Nanopartículas Metálicas , Nanoestruturas , DNA/química , Ouro/química , Nanoestruturas/química , Nanopartículas Metálicas/química , Química Click , Tamanho da Partícula
9.
Nanoscale ; 16(16): 7874-7883, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38563323

RESUMO

Anisotropic gold (Au) nanostructures have been widely explored for various nanomedicine applications. While these nanomaterials have shown great promise for disease theranostics, particularly for cancer diagnosis and treatment, the utilization and clinical translation of anisotropic Au nanostructures have been limited by their high phagocytic uptake and clearance and low cancer targeting specificity. Numerous efforts have thus been made toward mitigating these challenges. Many conventional strategies, however, rely on all-synthetic materials, involve complex chemical processes, or have low product throughput and reproducibility. Herein, by integrating cell membrane coating and microfluidic technologies, a high-throughput bioinspired approach for synthesizing biomimetic anisotropic Au nanostructures with minimized phagocytic uptake and improved cancer cell targeting is reported. Through continuous hydrodynamic flow focusing, mixing, and sonication, Au nanostructures are encapsulated within the macrophage and cancer cell membrane vesicles effectively. The fabricated nanostructures are uniform and highly stable in serum. Importantly, the macrophage membrane vesicle-encapsulated Au nanostructures can be preferentially internalized by breast cancer cells, but not by macrophages. Overall, this study has demonstrated the feasibility of employing an integrated microfluidic-sonication technique to formulate uniform and highly stable biomimetic anisotropic nanostructures for enhanced cancer theranostic applications.


Assuntos
Membrana Celular , Ouro , Ouro/química , Humanos , Anisotropia , Membrana Celular/metabolismo , Membrana Celular/química , Animais , Camundongos , Macrófagos/metabolismo , Macrófagos/citologia , Nanopartículas Metálicas/química , Células RAW 264.7 , Linhagem Celular Tumoral , Nanoestruturas/química , Células MCF-7
10.
Proc Natl Acad Sci U S A ; 121(16): e2321498121, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38593077

RESUMO

In recent decades, peptide amphiphiles (PAs) have established themselves as promising self-assembling bioinspired materials in a wide range of medical fields. Herein, we report a dual-therapeutic system constituted by an antimicrobial PA and a cylindrical protease inhibitor (LJC) to achieve broad antimicrobial spectrum and to enhance therapeutic efficacy. We studied two strategies: PA-LJC nanostructures (Encapsulation) and PA nanostructures + free LJC (Combination). Computational modeling using a molecular theory for amphiphile self-assembly captures and explains the morphology of PA-LJC nanostructures and the location of encapsulated LJC in agreement with transmission electron microscopy and two-dimensional (2D) NMR observations. The morphology and release profile of PA-LJC assemblies are strongly correlated to the PA:LJC ratio: high LJC loading induces an initial burst release. We then evaluated the antimicrobial activity of our nanosystems toward gram-positive and gram-negative bacteria. We found that the Combination broadens the spectrum of LJC, reduces the therapeutic concentrations of both agents, and is not impacted by the inoculum effect. Further, the Encapsulation provides additional benefits including bypassing water solubility limitations of LJC and modulating the release of this molecule. The different properties of PA-LJC nanostructures results in different killing profiles, and reduced cytotoxicity and hemolytic activity. Meanwhile, details in membrane alterations caused by each strategy were revealed by various microscopy and fluorescent techniques. Last, in vivo studies in larvae treated by the Encapsulation strategy showed better antimicrobial efficacy than polymyxin B. Collectively, this study established a multifunctional platform using a versatile PA to act as an antibiotic, membrane-penetrating assistant, and slow-release delivery vehicle.


Assuntos
Anti-Infecciosos , Nanoestruturas , Antibacterianos/farmacologia , Antibacterianos/química , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Nanoestruturas/química
11.
Theranostics ; 14(6): 2290-2303, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38646651

RESUMO

Background: Neoantigen nanovaccine has been recognized as a promising treatment modality for personalized cancer immunotherapy. However, most current nanovaccines are carrier-dependent and the manufacturing process is complicated, resulting in potential safety concerns and suboptimal codelivery of neoantigens and adjuvants to antigen-presenting cells (APCs). Methods: Here we report a facile and general methodology for nanoassembly of peptide and oligonucleotide by programming neoantigen peptide with a short cationic module at N-terminus to prepare nanovaccine. The programmed peptide can co-assemble with CpG oligonucleotide (TLR9 agonist) into monodispersed nanostructures without the introduction of artificial carrier. Results: We demonstrate that the engineered nanovaccine promoted the codelivery of neoantigen peptides and adjuvants to lymph node-residing APCs and instigated potent neoantigen-specific T-cell responses, eliciting neoantigen-specific antitumor immune responses with negligible systemic toxicity. Furthermore, the antitumor T-cell immunity is profoundly potentiated when combined with anti-PD-1 therapy, leading to significant inhibition or even complete regression of established melanoma and MC-38 colon tumors. Conclusions: Collectively, this work demonstrates the feasibility and effectiveness of personalized cancer nanovaccine preparation with high immunogenicity and good biosafety by programming neoantigen peptide for nanoassembly with oligonucleotides without the aid of artificial carrier.


Assuntos
Antígenos de Neoplasias , Vacinas Anticâncer , Peptídeos , Vacinas Anticâncer/imunologia , Vacinas Anticâncer/administração & dosagem , Animais , Camundongos , Antígenos de Neoplasias/imunologia , Peptídeos/imunologia , Peptídeos/química , Camundongos Endogâmicos C57BL , Oligodesoxirribonucleotídeos/administração & dosagem , Oligodesoxirribonucleotídeos/imunologia , Oligodesoxirribonucleotídeos/química , Células Apresentadoras de Antígenos/imunologia , Linhagem Celular Tumoral , Imunoterapia/métodos , Humanos , Feminino , Linfócitos T/imunologia , Nanoestruturas/química , Neoplasias do Colo/imunologia , Neoplasias do Colo/terapia , Neoplasias do Colo/tratamento farmacológico
12.
Protein Sci ; 33(5): e4983, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38659173

RESUMO

Serum amyloid A (SAA) is a highly conserved acute-phase protein that plays roles in activating multiple pro-inflammatory pathways during the acute inflammatory response and is commonly used as a biomarker of inflammation. It has been linked to beneficial roles in tissue repair through improved clearance of lipids and cholesterol from sites of damage. In patients with chronic inflammatory diseases, elevated levels of SAA may contribute to increased severity of the underlying condition. The majority of circulating SAA is bound to lipoproteins, primarily high-density lipoprotein (HDL). Interaction with HDL not only stabilizes SAA but also alters its functional properties, likely through altered accessibility of protein-protein interaction sites on SAA. While high-resolution structures for lipid-free, or apo-, forms of SAA have been reported, their relationship with the HDL-bound form of the protein, and with other possible mechanisms of SAA binding to lipids, has not been established. Here, we have used multiple biophysical techniques, including SAXS, TEM, SEC-MALS, native gel electrophoresis, glutaraldehyde crosslinking, and trypsin digestion to characterize the lipid-free and lipid-bound forms of SAA. The SAXS and TEM data show the presence of soluble octamers of SAA with structural similarity to the ring-like structures reported for lipid-free ApoA-I. These SAA octamers represent a previously uncharacterized structure for lipid-free SAA and are capable of scaffolding lipid nanodiscs with similar morphology to those formed by ApoA-I. The SAA-lipid nanodiscs contain four SAA molecules and have similar exterior dimensions as the lipid-free SAA octamer, suggesting that relatively few conformational rearrangements may be required to allow SAA interactions with lipid-containing particles such as HDL. This study suggests a new model for SAA-lipid interactions and provides new insight into how SAA might stabilize protein-lipid nanodiscs or even replace ApoA-I as a scaffold for HDL particles during inflammation.


Assuntos
Proteína Amiloide A Sérica , Proteína Amiloide A Sérica/química , Proteína Amiloide A Sérica/metabolismo , Humanos , Lipoproteínas HDL/química , Lipoproteínas HDL/metabolismo , Nanoestruturas/química , Modelos Moleculares , Apolipoproteína A-I/química , Apolipoproteína A-I/metabolismo , Ligação Proteica
13.
Biotechnol J ; 19(4): e2300308, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38651249

RESUMO

It was previously demonstrated that polypod-like nanostructured DNA (polypodna) comprising three or more oligodeoxynucleotides (ODNs) were useful for the delivery of ODNs containing cytosine-phosphate-guanine (CpG) motifs, or CpG ODNs, to immune cells. Although the immunostimulatory activity of single-stranded CpG ODNs is highly dependent on CpG motif sequence and position, little is known about how the position of the motif affects the immunostimulatory activity of CpG motif-containing nanostructured DNAs. In the present study, four series of polypodna were designed, each comprising a CpG ODN with one potent CpG motif at varying positions and 2-5 CpG-free ODNs, and investigated their immunostimulatory activity using Toll-like receptor-9 (TLR9)-positive murine macrophage-like RAW264.7 cells. Polypodnas with the CpG motif in the 5'-overhang induced more tumor necrosis factor-α release than those with the motif in the double-stranded region, even though their cellular uptake were similar. Importantly, the rank order of the immunostimulatory activity of single-stranded CpG ODNs changed after their incorporation into polypodna. These results indicate that the CpG ODN sequence as well as the motif location in nanostructured DNAs should be considered for designing the CpG motif-containing nanostructured DNAs for immune stimulation.


Assuntos
DNA , Nanoestruturas , Oligodesoxirribonucleotídeos , Receptor Toll-Like 9 , Camundongos , Nanoestruturas/química , Animais , Células RAW 264.7 , Oligodesoxirribonucleotídeos/química , Oligodesoxirribonucleotídeos/farmacologia , DNA/química , DNA/imunologia , Adjuvantes Imunológicos/química , Adjuvantes Imunológicos/farmacologia , Ilhas de CpG , Fator de Necrose Tumoral alfa/metabolismo , Macrófagos/imunologia , Macrófagos/efeitos dos fármacos
14.
Inorg Chem ; 63(16): 7199-7205, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38602179

RESUMO

A nine-metal Zn(II)-Eu(III) nanoring 1 with a diameter of about 2.3 nm was constructed by the use of a long-chain Schiff base ligand. It shows a luminescence response to neopterin (Neo) through the enhancement of lanthanide emission with high selectivity and sensitivity, which can be used to quantitatively analyze the concentrations of Neo in fetal calf serum and urine. The luminescence sensing of 1 to Neo is temperature-dependent, and it displays more obvious response behavior at lower temperatures. Filter paper strips bearing 1 can be used to qualitatively detect Neo by the color change from chartreuse to red under a UV lamp. The limit of detection is as low as 3.77 × 10-2 nM.


Assuntos
Európio , Nanoestruturas , Neopterina , Temperatura , Zinco , Zinco/química , Zinco/análise , Neopterina/análise , Neopterina/urina , Neopterina/sangue , Európio/química , Nanoestruturas/química , Humanos , Luminescência , Medições Luminescentes , Biomarcadores/análise , Biomarcadores/sangue , Limite de Detecção , Animais
15.
Sci Adv ; 10(16): eadk0217, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38630809

RESUMO

Biological phenomena, from enzymatic catalysis to synaptic transmission, originate in the structural transformations of biomolecules and biomolecular assemblies in liquid water. However, directly imaging these nanoscopic dynamics without probes or labels has been a fundamental methodological challenge. Here, we developed an approach for "electron videography"-combining liquid phase electron microscopy with molecular modeling-with which we filmed the nanoscale structural fluctuations of individual, suspended, and unlabeled membrane protein nanodiscs in liquid. Systematic comparisons with biochemical data and simulation indicate the graphene encapsulation involved can afford sufficiently reduced effects of the illuminating electron beam for these observations to yield quantitative fingerprints of nanoscale lipid-protein interactions. Our results suggest that lipid-protein interactions delineate dynamically modified membrane domains across unexpectedly long ranges. Moreover, they contribute to the molecular mechanics of the nanodisc as a whole in a manner specific to the protein within. Overall, this work illustrates an experimental approach to film, quantify, and understand biomolecular dynamics at the nanometer scale.


Assuntos
Elétrons , Nanoestruturas , Proteínas de Membrana/química , Simulação de Dinâmica Molecular , Microscopia Eletrônica , Lipídeos/química , Bicamadas Lipídicas/química , Nanoestruturas/química
16.
J Colloid Interface Sci ; 666: 434-446, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38608638

RESUMO

Bacterial infections are among the most significant causes of death in humans. Chronic misuse or uncontrolled use of antibiotics promotes the emergence of multidrug-resistant superbugs that threaten public health through the food chain and cause environmental pollution. Based on the above considerations, copper selenide nanosheets (CuSe NSs) with photothermal therapy (PTT)- and photodynamic therapy (PDT)-related properties have been fabricated. These CuSe NSs possess enhanced PDT-related properties and can convert O2 into highly toxic reactive oxygen species (ROS), which can cause significant oxidative stress and damage to bacteria. In addition, CuSe NSs can efficiently consume glutathione (GSH) at bacterial infection sites, thus further enhancing their sterilization efficacy. In vitro antibacterial experiments with near-infrared (NIR) irradiation have shown that CuSe NSs have excellent photothermal bactericidal properties. These experiments also showed that CuSe NSs exerted excellent bactericidal effects on wounds infected with methicillin-resistant Staphylococcus aureus (MRSA) and significantly promoted the healing of infected wounds. Because of their superior biological safety, CuSe NSs are novel copper-based antimicrobial agents that are expected to enter clinical trials, serving as a modern approach to the major problem of treating bacterially infected wounds.


Assuntos
Antibacterianos , Cobre , Staphylococcus aureus Resistente à Meticilina , Testes de Sensibilidade Microbiana , Nanoestruturas , Terapia Fototérmica , Cobre/química , Cobre/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Animais , Nanoestruturas/química , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Humanos , Propriedades de Superfície , Tamanho da Partícula , Selênio/química , Selênio/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Infecções Estafilocócicas/tratamento farmacológico
17.
Sci Rep ; 14(1): 9168, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649777

RESUMO

Fluorinated graphene, a two-dimensional nanomaterial composed of three atomic layers, a central carbon layer sandwiched between two layers of fluorine atoms, has attracted considerable attention across various fields, particularly for its potential use in biomedical applications. Nonetheless, scant effort has been devoted to assessing the potential toxicological implications of this nanomaterial. In this study, we scrutinize the potential impact of fluorinated graphene on a protein model, HP35 by utilizing extensive molecular dynamics (MD) simulation methods. Our MD results elucidate that upon adsorption to the nanomaterial, HP35 undergoes a denaturation process initiated by the unraveling of the second helix of the protein and the loss of the proteins hydrophobic core. In detail, substantial alterations in various structural features of HP35 ensue, including alterations in hydrogen bonding, Q value, and RMSD. Subsequent analyses underscore that hydrophobic and van der Waals interactions (predominant), alongside electrostatic energy (subordinate), exert influence over the adsorption of HP35 on the fluorinated graphene surface. Mechanistic scrutiny attests that the unrestrained lateral mobility of HP35 on the fluorinated graphene nanomaterial primarily causes the exposure of HP35's hydrophobic core, resulting in the eventual structural denaturation of HP35. A trend in the features of 2D nanostructures is proposed that may facilitate the denaturation process. Our findings not only substantiate the potential toxicity of fluorinated graphene but also unveil the underlying molecular mechanism, which thereby holds significance for the prospective utilization of such nanomaterials in the field of biomedicine.


Assuntos
Grafite , Ligação de Hidrogênio , Simulação de Dinâmica Molecular , Proteínas de Neurofilamentos , Fragmentos de Peptídeos , Conformação Proteica em alfa-Hélice , Grafite/química , Grafite/toxicidade , Interações Hidrofóbicas e Hidrofílicas , Desdobramento de Proteína/efeitos dos fármacos , Halogenação , Adsorção , Nanoestruturas/química , Nanoestruturas/toxicidade
18.
Ultrason Sonochem ; 105: 106858, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38564910

RESUMO

Zinc sulfide/graphitic Carbon Nitride binary nanosheets were synthesized by using a novel sonochemical pathway with high electrocatalytic ability. The as- obtained samples were characterized by various analytical methods such as Transmission Electron Microscopy (TEM), Field emission scanning electron microscopy (FESEM), Energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction analysis (XRD), and X-ray photoelectron spectroscopy (XPS) to evaluate the properties of ZnS@CNS synthesized by this new route. Subsequently, the electrical and electrochemical performance of the proposed electrodes were characterized by using EIS and CV to establish an electroactive ability of the nanocomposites. The complete properties like structural and physical of ZnS@CNS were analyzed. As-prepared binary nanocomposite was applied towards the detection of anticancer drug (flutamide) by various electrochemical methods such as cyclic voltammetry (CV), differential pulse voltammetry (DPV) and amperometry. The glassy carbon electrode modified with a ZnS@CNS composite demonstrates a remarkable electrocatalytic efficiency for detecting flutamide in a pH 7.0 (PBS). The composite modified electrode shows synergistic effect of ZnS and CNS catalyst. The electrochemical sensing performance of the linear range was improved significantly due to high electroactive sites and rapid electron transport pathways. Crucially, the electrochemical method was successfully demonstrated in biological fluids which reveals its potential real-time applicability in the analysis of drug.


Assuntos
Antineoplásicos , Eletrodos , Grafite , Compostos de Nitrogênio , Sulfetos , Ondas Ultrassônicas , Compostos de Zinco , Compostos de Zinco/química , Sulfetos/química , Antineoplásicos/química , Grafite/química , Flutamida/análise , Flutamida/química , Técnicas Eletroquímicas/métodos , Técnicas de Química Sintética , Eletroquímica , Limite de Detecção , Catálise , Nanocompostos/química , Nanoestruturas/química
19.
Nanoscale ; 16(16): 7786-7824, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38568434

RESUMO

Nanozymes, as a type of nanomaterials with enzymatic catalytic activity, have demonstrated tremendous potential in cancer treatment owing to their unique biomedical properties. However, the heterogeneity of tumors and the complex tumor microenvironment pose significant challenges to the in vivo catalytic efficacy of traditional nanozymes. Drawing inspiration from natural enzymes, scientists are now using biomimetic design to build nanozymes from the ground up. This approach aims to replicate the key characteristics of natural enzymes, including active structures, catalytic processes, and the ability to adapt to the tumor environment. This achieves selective optimization of nanozyme catalytic performance and therapeutic effects. This review takes a deep dive into the use of these biomimetically designed nanozymes in cancer treatment. It explores a range of biomimetic design strategies, from structural and process mimicry to advanced functional biomimicry. A significant focus is on tweaking the nanozyme structures to boost their catalytic performance, integrating them into complex enzyme networks similar to those in biological systems, and adjusting functions like altering tumor metabolism, reshaping the tumor environment, and enhancing drug delivery. The review also covers the applications of specially designed nanozymes in pan-cancer treatment, from catalytic therapy to improved traditional methods like chemotherapy, radiotherapy, and sonodynamic therapy, specifically analyzing the anti-tumor mechanisms of different therapeutic combination systems. Through rational design, these biomimetically designed nanozymes not only deepen the understanding of the regulatory mechanisms of nanozyme structure and performance but also adapt profoundly to tumor physiology, optimizing therapeutic effects and paving new pathways for innovative cancer treatment.


Assuntos
Materiais Biomiméticos , Nanoestruturas , Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/terapia , Materiais Biomiméticos/química , Materiais Biomiméticos/uso terapêutico , Nanoestruturas/química , Nanoestruturas/uso terapêutico , Catálise , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Animais , Microambiente Tumoral/efeitos dos fármacos , Biomimética
20.
Anal Chem ; 96(16): 6202-6208, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38598750

RESUMO

New strategies for accurate and reliable detection of adenosine triphosphate (ATP) with portable devices are significant for biochemical analysis, while most recently reported approaches cannot satisfy the detection accuracy and independent of large instruments simultaneously, which are unsuitable for fast, simple, and on-site ATP monitoring. Herein, a unique, convenient, and label-free point-of-care sensing strategy based on novel copper coordination polymer nanoflowers (CuCPNFs) was fabricated for multimode (UV-vis, photothermal, and RGB values) onsite ATP determination with high selectivity, sensitivity, and accuracy. The resulting CuCPNFs with a 3D hierarchical structure exhibit the ATP-triggered decomposition behavior because the competitive coordination between ATP and the copper ions of CuCPNFs can result in the formation of ATP-Cu, which reveals preeminent peroxidase mimics activity and can accelerate the oxidation of 3, 3', 5, 5'-tetramethylbenzidine (TMB) to form oxTMB. During this process, the detection system displayed not only color changes but also a strong NIR laser-driven photothermal effect. Thus, the photothermal and color signal variations are easily monitored by a portable thermometer and a smartphone. This multimode point-of-care platform can meet the requirements of onsite, without bulky equipment, accuracy, and reliability all at once, greatly enhancing its application in practice and paving a new way in ATP analysis.


Assuntos
Trifosfato de Adenosina , Cobre , Polímeros , Cobre/química , Trifosfato de Adenosina/análise , Polímeros/química , Sistemas Automatizados de Assistência Junto ao Leito , Humanos , Nanoestruturas/química , Limite de Detecção , Colorimetria , Benzidinas/química , Testes Imediatos
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