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1.
Sci Rep ; 12(1): 13411, 2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35927441

RESUMO

Neurological disorders and nerve injuries, such as spinal cord injury, stroke, and multiple sclerosis can result in the loss of muscle function. Electrical stimulation of the neuronal cells is the currently available clinical treatment in this regard. As an effective energy harvester, the triboelectric nanogenerators (TENG) can be used for self-powered neural/muscle stimulations because the output of the TENG provides stimulation pulses for nerves. In the present study, using a computational modelling approach, the effect of surface micropatterns on the electric field distribution, induced voltage and capacitance of the TENG structures have been investigated. By incorporating the effect of the TENG inside the mathematical model of neuron's electrical behavior (cable equation with Hodgkin-Huxley model), its impact on the electrical behavior of the neurons has been studied. The results show that the TENG operates differently with various surface modifications. The performance of the TENG in excitation of neurons depends on the contact and release speed of its electrodes accordingly.


Assuntos
Fontes de Energia Elétrica , Nanotecnologia , Simulação por Computador , Eletricidade , Nanotecnologia/métodos , Neurônios
3.
J Nanobiotechnology ; 20(1): 361, 2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35918688

RESUMO

Ocular drug delivery is one of the most challenging endeavors among the various available drug delivery systems. Despite having suitable drugs for the treatment of ophthalmic disease, we have not yet succeeded in achieving a proper drug delivery approach with the least adverse effects. Nanotechnology offers great opportunities to overwhelm the restrictions of common ocular delivery systems, including low therapeutic effects and adverse effects because of invasive surgery or systemic exposure. The present review is dedicated to highlighting and updating the recent achievements of nano-based technologies for ocular disease diagnosis and treatment. While further effort remains, the progress illustrated here might pave the way to new and very useful ocular nanomedicines.


Assuntos
Sistemas de Liberação de Medicamentos , Oftalmopatias , Olho , Oftalmopatias/diagnóstico , Oftalmopatias/tratamento farmacológico , Humanos , Nanomedicina , Nanotecnologia
4.
Proc Natl Acad Sci U S A ; 119(32): e2200019119, 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35914130

RESUMO

The nanoscale structure and dynamics of proteins on surfaces has been extensively studied using various imaging techniques, such as transmission electron microscopy and atomic force microscopy (AFM) in liquid environments. These powerful imaging techniques, however, can potentially damage or perturb delicate biological material and do not provide chemical information, which prevents a fundamental understanding of the dynamic processes underlying their evolution under physiological conditions. Here, we use a platform developed in our laboratory that enables acquisition of infrared (IR) spectroscopy and AFM images of biological material in physiological liquids with nanometer resolution in a cell closed by atomically thin graphene membranes transparent to IR photons. In this work, we studied the self-assembly process of S-layer proteins at the graphene-aqueous solution interface. The graphene acts also as the membrane separating the solution containing the proteins and Ca2+ ions from the AFM tip, thus eliminating sample damage and contamination effects. The formation of S-layer protein lattices and their structural evolution was monitored by AFM and by recording the amide I and II IR absorption bands, which reveal the noncovalent interaction between proteins and their response to the environment, including ionic strength and solvation. Our measurement platform opens unique opportunities to study biological material and soft materials in general.


Assuntos
Glicoproteínas de Membrana , Microscopia de Força Atômica , Nanotecnologia , Espectrofotometria Infravermelho , Amidas/química , Cálcio , Grafite/química , Glicoproteínas de Membrana/química , Glicoproteínas de Membrana/metabolismo , Glicoproteínas de Membrana/ultraestrutura , Concentração Osmolar , Fótons , Solventes/química , Água/química
5.
J Cell Sci ; 135(15)2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35942913

RESUMO

Cellular and tissue biosystems emerge from the assembly of their constituent molecules and obtain a set of specific material properties. To measure these properties and understand how they influence cellular function is a central goal of mechanobiology. From a bottoms-up, physics or engineering point-of-view, such systems are a composition of basic mechanical elements. However, the sheer number and dynamic complexity of them, including active molecular machines and their emergent properties, makes it currently intractable to calculate how biosystems respond to forces. Because many diseases result from an aberrant mechanotransduction, it is thus essential to measure this response. Recent advances in the technology of optical tweezers have broadened their scope from single-molecule applications to measurements inside complex cellular environments, even within tissues and animals. Here, we summarize the basic optical trapping principles, implementations and calibration procedures that enable force measurements using optical tweezers directly inside cells of living animals, in combination with complementary techniques. We review their versatility to manipulate subcellular organelles and measure cellular frequency-dependent mechanics in the piconewton force range from microseconds to hours. As an outlook, we address future challenges to fully unlock the potential of optical tweezers for mechanobiology.


Assuntos
Mecanotransdução Celular , Pinças Ópticas , Animais , Fenômenos Fisiológicos Celulares , Nanotecnologia , Organelas
6.
Methods Mol Biol ; 2516: 157-167, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35922627

RESUMO

Direct, live imaging of protein-DNA interactions under physiological conditions is invaluable for understanding the mechanism and kinetics of binding and understanding the topological changes of the DNA strand. The DNA origami technology allows for precise placement of target molecules in a designed nanostructure. Here, we describe a protocol for the self-assembly of DNA origami frames with 2 stretched DNA sequences containing the binding site of a transcription factor, i.e., the Protein FadR, which is a TetR-family tanscription factor regulator for fatty acid metabolism in the archaeal organism Sulfolobus acidocaldarius. These frames can be used to study the dynamics of transcription factor binding using high-speed AFM and obtain mechanistic insights into the mechanism of action of transcription factors.


Assuntos
DNA , Nanoestruturas , DNA/química , Microscopia de Força Atômica/métodos , Nanoestruturas/química , Nanotecnologia/métodos , Conformação de Ácido Nucleico , Fatores de Transcrição
7.
Chempluschem ; 87(8): e202200127, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35914775

RESUMO

Numerous nucleic acid nanostructures of unique addressability and programmability have been fabricated for emerging applications. Structural characterization with atomic force microscopy and electron microscopy can provide information on the structural morphology and precision of these nanostructures. However, either structural information of native nucleic acid nanostructures in hydrated environment or the availability of addressable sites on these nanostructures could not be determined. Alternatively, DNA points accumulation for imaging in nanoscale topography (DNA-PAINT) enables direct optical visualization of nucleic acid nanostructures in native forms, as well as evaluation of the accessibility of addressable sites on them. In this Review, the working principle of DNA-PAINT is introduced, followed by the summary on advances of DNA-PAINT characterization of various nucleic acid nanostructures. Finally, the current challenges and prospects for DNA-PAINT characterization are presented. We envision DNA-PAINT to be a potent characterization tool for functional nanomaterials.


Assuntos
Nanoestruturas , Ácidos Nucleicos , DNA/química , Microscopia de Fluorescência/métodos , Nanoestruturas/química , Nanotecnologia/métodos
8.
Nature ; 608(7922): S1, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35948720
9.
Nature ; 608(7922): S12-S13, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35948722
10.
Nature ; 608(7922): S4-S5, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35948723

Assuntos
Nanotecnologia
11.
J Vis Exp ; (185)2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35938845

RESUMO

Cellular membranes are highly crowded environments for biomolecular reactions and signaling. Yet, most in vitro experiments probing protein interaction with lipids employ naked bilayer membranes. Such systems lack the complexities of crowding by membrane-embedded proteins and glycans and exclude the associated volume effects encountered on cellular membrane surfaces. Also, the negatively charged glass surface onto which the lipid bilayers are formed prevents the free diffusion of transmembrane biomolecules. Here, we present a well-characterized polymer-lipid membrane as a mimic for crowded lipid membranes. This protocol utilizes polyethylene glycol (PEG)-conjugated lipids as a generalized approach for incorporating crowders into the supported lipid bilayer (SLB). First, a cleaning procedure of the microscopic slides and coverslips for performing single-molecule experiments is presented. Next, methods for characterizing the PEG-SLBs and performing single-molecule experiments of the binding, diffusion, and assembly of biomolecules using single-molecule tracking and photobleaching are discussed. Finally, this protocol demonstrates how to monitor the nanopore assembly of bacterial pore-forming toxin Cytolysin A (ClyA) on crowded lipid membranes with single-molecule photobleaching analysis. MATLAB codes with example datasets are also included to perform some of the common analyses such as particle tracking, extracting diffusive behavior, and subunit counting.


Assuntos
Bicamadas Lipídicas , Polímeros , Membrana Celular/química , Difusão , Bicamadas Lipídicas/química , Proteínas de Membrana/química , Nanotecnologia , Polietilenoglicóis/química , Polímeros/química
12.
Small ; 18(30): e2201417, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35801427

RESUMO

Plants are anatomically and physiologically different from humans and animals; however, there are several possibilities to utilize the unique structures and physiological systems of plants and adapt them to new emerging technologies through a strategic biomimetic approach. Moreover, plants provide safe and sustainable results that can potentially solve the problem of mass-producing practical materials with hazardous and toxic side effects, particularly in the biomedical field, which requires high biocompatibility. In this review, it is investigated how micro-nanostructures available in plants (e.g., nanoparticles, nanofibers and their composites, nanoporous materials, and natural micromotors) are adapted and utilized in the design of suitable materials for a micro-nanorobot platform. How plants' work on micro- and nanoscale systems (e.g., surface roughness, osmotically induced movements such as nastic and tropic, and energy conversion and harvesting) that are unique to plants, can provide functionality on the platform and become further prospective resources are examined. Furthermore, implementation across organisms and fields, which is promising for future practical applications of the plant-actuated micro-nanorobot platform, especially on biomedical applications, is discussed. Finally, the challenges following its implementation in the micro-nanorobot platform are also presented to provide advanced adaptation in the future.


Assuntos
Nanopartículas , Nanoestruturas , Animais , Biomimética , Humanos , Nanoestruturas/química , Nanotecnologia/métodos
13.
Chem Commun (Camb) ; 58(59): 8290-8293, 2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35791867

RESUMO

The single molecular conductance of viologen derivative VSMe and supramolecular compound VSMe-PA[5] (pillararene[5]) was investigated. The difference of their conductance demonstrated the gating effect of cation-π interaction. Theoretical calculations showed that the higher conductance of VSMe-PA[5] is a result of the planar structure of the VSMe component and the narrowed HOMO-LUMO bandgap of VSMe-PA[5], which is due to the cation-π interaction between the VSMe and PA[5] components.


Assuntos
Nanotecnologia , Cátions
14.
Drug Deliv ; 29(1): 2442-2458, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35892224

RESUMO

A boom in respiratory tract infection cases has inflicted a socio-economic burden on the healthcare system worldwide, especially in developing countries. Limited alternative therapeutic options have posed a major threat to human health. Nanotechnology has brought an immense breakthrough in the pharmaceutical industry in a jiffy. The vast applications of nanotechnology ranging from early diagnosis to treatment strategies are employed for respiratory tract infections. The research avenues explored a multitude of nanosystems for effective drug delivery to the target site and combating the issues laid through multidrug resistance and protective niches of the bacteria. In this review a brief introduction to respiratory diseases and multifaceted barriers imposed by bacterial infections are enlightened. The manuscript reviewed different nanosystems, i.e. liposomes, solid lipid nanoparticles, polymeric nanoparticles, dendrimers, nanogels, and metallic (gold and silver) which enhanced bactericidal effects, prevented biofilm formation, improved mucus penetration, and site-specific delivery. Moreover, most of the nanotechnology-based recent research is in a preclinical and clinical experimental stage and safety assessment is still challenging.


Assuntos
Nanopartículas , Infecções Respiratórias , Sistemas de Liberação de Medicamentos , Humanos , Lipossomos , Nanopartículas/uso terapêutico , Nanotecnologia , Infecções Respiratórias/tratamento farmacológico
15.
Sci Rep ; 12(1): 13081, 2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35906365

RESUMO

Periodic subwavelength apertures have the ability to passively detect variations in the dielectric properties of the local sample environment through modification of the plasmon resonances associated with these structures. The resulting resonance peak can effectively provide a 'fingerprint' indicative of the dielectric properties of the medium within the near-surface region. Here we report on the use of bimodal silver-based plasmonic colour filters for molecular sensing. Firstly, by exploring the optical output of these devices as a function of the incident polarisation for a range of different analytes of known refractive index, we were able to both maximise and quantify their sensitivity. We then apply this concept to the real-time monitoring of the formation of self-assembled monolayers based on detection of the optical output using a spectrometer. This highlights the potential for bimodal plasmonic devices to be able to dynamically monitor variations in the local environment down to the level of single molecules without the need for specific functionalisation or labelling. Advantages of using this technique include the ability for these devices to be miniaturised and to dynamically tailor their optical output permitting the analysis of very small sample volumes and maximise their dynamic range for a specific analyte.


Assuntos
Técnicas Biossensoriais , Ressonância de Plasmônio de Superfície , Técnicas Biossensoriais/métodos , Nanotecnologia/métodos , Refratometria , Ressonância de Plasmônio de Superfície/métodos
16.
Sci Rep ; 12(1): 13080, 2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35906371

RESUMO

With the development and progress of nanotechnology, the prospect of using nanorobots to achieve targeted drug delivery is becoming possible. Although nanorobots can potentially improve nano-drug delivery systems, there remains a significant challenge to fabricating magnetically controllable nanorobots with a size suitable for drug delivery in complex in vivo environments. Most of the current research focused on the preparation and functionalization of microscale and milliscale robots due to the relative difficulties in fabricating nanoscale robots. To address this problem and move towards in vivo applications, this study uses electron beam lithography to fabricate achiral planar L-shaped nanorobots that are biocompatible with immune cells. Their minimal planar geometry enabled nanolithography to fabricate nanorobots with a minimum feature size down to 400 nm. Using an integrated imaging and control system, the locomotive behavior of the L-shaped nanorobots in a fluidic environment was studied by examining their velocity profiles and trajectories. Furthermore, the nanorobots exhibit excellent cell compatibility with various types of cells, including macrophage cells. Finally, the long-term cell culture medium immersion test demonstrated that the L-shaped nanorobots have robust stability. This work will demonstrate the potential to use these nanorobots to operate in vivo without triggering immune cell responses.


Assuntos
Elétrons , Nanotecnologia , Sistemas de Liberação de Medicamentos , Macrófagos , Magnetismo
18.
Methods Mol Biol ; 2473: 367-383, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35819776

RESUMO

Numerous proteins directly or indirectly bind membranes to exert their roles in a wide variety of biological processes. Such membrane binding often occurs in the presence of an external mechanical force. It remains challenging to quantify these interactions using traditional experimental approaches based on a large number of molecules, due to ensemble averaging or the lack of mechanical force. Here we described a new single-molecule approach based on high-resolution optical tweezers to characterize protein-membrane interactions. A single membrane binding protein is attached to the lipid bilayer coated on a silica bead via a flexible polypeptide linker, tethered to another bead via a long DNA handle, and pulled away from the bilayer using optical tweezers. Dynamic protein binding and unbinding is detected by the corresponding changes in the extension of the protein-DNA tether with high spatiotemporal resolution, which reveals the membrane binding affinity, kinetics, and intermediates. We demonstrated the method using C2 domains of extended synaptotagmin 2 (E-Syt2) with a detailed protocol. The method can be widely applied to investigate complex protein-membrane interactions under well-controlled experimental conditions.


Assuntos
Nanotecnologia , Pinças Ópticas , Fenômenos Biofísicos , DNA , Bicamadas Lipídicas
19.
J Colloid Interface Sci ; 625: 774-784, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35777092

RESUMO

Peroxymonosulfate (PMS)-based Fenton-like reaction is an effective technique for the pollutant degradation, and the Co-based metal organic frameworks displayed the excellent activity for the PMS activation. Nevertheless, how to further improve the catalytic activity, suppress the leaching of toxic cobalt ions, and realize the rapid separation were still challenges for practical application. In this work, a novel solution was proposed: encapsulating Fe3O4 and Prussian blue analogue (PBA) into the polypyrrole (PPy) shell and constructing a "double-yolk egg-like" Fe3O4/PBA@PPy as a nanoreactor. In Fe3O4/PBA@PPy-10, the catalytic performance was remarkably enhanced with the help of confinement effect, and the degradation rate (0.38 L·min·mol-1) was 5.1 times than that of reference Fe3O4/PBA-10 (0.074 L·min·mol-1). In addition, the concentration of leached cobalt ions was reduced to only 0.174 mg/L by the protective function from the PPy shell. Moreover, the nanoreactor could be magnetically separated from the reaction solution due to the encapsulation of Fe3O4 nanospheres, and 84.5% of activity still preserved after the 4th cycle. The main active species involved in Fe3O4/PBA@PPy-10 system was 1O2, while that in reference Fe3O4/PBA-10 system was OH. Electron spin resonance analysis and radical trapping experiment revealed that the different catalytic mechanisms were attributed to the confinement effect inside the hollow cavity. This work not only presents a feasible way to prepare rarely-reported double-yolk egg-like nanoreactor, but also provides a new insight to solve the bottlenecks in Fenton-like reaction.


Assuntos
Polímeros , Pirróis , Catálise , Cobalto , Nanotecnologia
20.
Assay Drug Dev Technol ; 20(5): 191-210, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35852823

RESUMO

Combination therapy has become much more effective in treating cancer because it produces combinatorial anticancer results, lowers specific drug-related toxicities, and inhibits multidrug resistivity through several modes of action. Combined drug delivery (CDD) to cancerous tissues, primarily based on nanotechnology, has developed as a viable method in recent years, surpassing various biomedical, biophysical, and biological obstacles that the body erects to prevent antitumor drugs from reaching their target tissues. In a combined strategy, the prolonged, regulated, and targeted administration of chemotherapeutic medicines improves therapeutic anticancer benefits while reducing drug-related adverse effects. CDD systems have several advantages over traditional drug systems, such as improved solubility, higher permeability for traveling through biomembranes, a significantly longer half-life to expand the treatment time, and low cytotoxicity. CDDs are mostly used to treat neurological, cardiovascular, neoplastic, infectious, and inflammatory diseases. Many CDDs are designed to enhance hydrophilicity to improve transportation inside or across biomembranes, particularly the cornea and skin. CDDs could be delivered to particular cells, organs, or tissues, resulting in increased bioavailability. The most widely utilized nanocarriers for CDDs of anticancer medicines are summarized in this review. This study also covers the chemical or enzymatic decomposition of CDDs and their bioactivity and pharmacokinetics. Additional clinical trials will enhance the usefulness of CDDs in treating drug-resistant tumors.


Assuntos
Antineoplásicos , Neoplasias , Antineoplásicos/química , Antineoplásicos/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Humanos , Nanotecnologia , Neoplasias/tratamento farmacológico , Preparações Farmacêuticas
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