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1.
Nat Commun ; 12(1): 2025, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33795690

RESUMEN

Circular dichroism (CD) has long been used to trace chiral molecular states and changes of protein configurations. In recent years, chiral plasmonic nanostructures have shown potential for applications ranging from pathogen sensing to novel optical materials. The plasmonic coupling of the individual elements of such metallic structures is a crucial prerequisite to obtain sizeable CD signals. We here identify and implement various coupling entities-chiral and achiral-to demonstrate chiral transfer over distances close to 100 nm. The coupling is realized by an achiral nanosphere situated between a pair of gold nanorods that are arranged far apart but in a chiral fashion using DNA origami. The transmitter particle causes a strong enhancement of the CD response, the emergence of an additional chiral feature at the resonance frequency of the nanosphere, and a redshift of the longitudinal plasmonic resonance frequency of the nanorods. Matching numerical simulations elucidate the intricate chiral optical fields in complex architectures.


Asunto(s)
Dicroismo Circular/métodos , ADN/química , Oro/química , Nanotubos/química , ADN/genética , ADN/ultraestructura , Nanopartículas del Metal/química , Nanopartículas del Metal/ultraestructura , Microscopía Electrónica de Transmisión , Nanoestructuras/química , Nanoestructuras/ultraestructura , Estereoisomerismo
2.
Inorg Chem ; 60(9): 6585-6599, 2021 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-33878862

RESUMEN

Silver vanadate nanorods (ß-AgVO3) with silver nanoparticles (Ag-NPs) decorated on the surface of the rods were synthesized by using simple hydrothermal technique and later anchored onto nitrogen-doped reduced graphene oxide (N-rGO) to make a novel nanocomposite. Experimental analyses were carried out to identify the electronic configuration by X-ray diffraction analysis, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy analysis, which revealed monoclinic patterns of the C12/m1 space group with Wulff construction forming beta silver vanadate (ß-AgVO3) crystals with optical density and phase transformations. Ag nucleation showed consistent results with metallic formation and electronic changes occurring in [AgO5] and [AgO3] clusters. Transmission electron microscopy and field-emission scanning electron microscopy with elemental mapping and EDX analysis of the morphology reveals the nanorod structure for ß-AgVO3 with AgNPs on the surface and sheets for N-rGO. Additionally, a novel electrochemical sensor is constructed by using Ag/AgVO3/N-rGO on screen-printed carbon paste electrodes for the detection of antiviral drug levofloxacin (LEV) which is used as a primary antibiotic in controlling COVID-19. Using differential pulse voltammetry, LEV is determined with a low detection limit of 0.00792 nm for a linear range of 0.09-671 µM with an ultrahigh sensitivity of 152.19 µA µM-1 cm-2. Furthermore, modified electrode performance is tested by real-time monitoring using biological and river samples.


Asunto(s)
Espectroscopía Dieléctrica/instrumentación , Espectroscopía Dieléctrica/métodos , Levofloxacino/análisis , Nanocompuestos/química , Antivirales/análisis , Antivirales/sangre , Antivirales/orina , Carbono/química , Electrodos , Grafito/química , Humanos , Levofloxacino/sangre , Levofloxacino/orina , Límite de Detección , Nanopartículas del Metal/química , Microscopía Electrónica de Transmisión , Nanotubos/química , Espectroscopía de Fotoelectrones , Plata/química , Compuestos de Plata/química , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría Raman , Comprimidos , Vanadatos/química , Difracción de Rayos X
3.
Int J Nanomedicine ; 16: 2789-2801, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33880024

RESUMEN

Objective: Gold nanorods (AuNRs) show great potential for versatile biomedical applications, such as stem cell therapy and bone tissue engineering. However, as an indispensable shape-directing agent for the growth of AuNRs, cetyltrimethylammonium bromide (CTAB) is not optimal for biological studies because it forms a cytotoxic bilayer on the AuNR surface, which interferes with the interactions with biological cells. Methods: Citrate-stabilized AuNRs with various aspect-ratios (Cit-NRI, Cit-NRII, and Cit-NRIII) were prepared by the combination of end-selective etching and poly(sodium 4-styrenesulfonate)-assisted ligand exchange method. Their effects on osteogenic differentiation of the pre-osteoblastic cell line (MC3T3-E1), rat bone marrow mesenchymal stem cells (rBMSCs), and human periodontal ligament progenitor cells (PDLPs) have been investigated. Potential signaling pathway of citrate-stabilized AuNRs-induced osteogenic effects was also investigated. Results: The experimental results showed that citrate-stabilized AuNRs have superior biocompatibility and undergo aspect-ratio-dependent osteogenic differentiation via expression of osteogenic marker genes, alkaline phosphatase (ALP) activity and formation of mineralized nodule. Furthermore, Wnt/ß-catenin signaling pathway might provide a potential explanation for the citrate-stabilized AuNRs-mediated osteogenic differentiation. Conclusion: These findings revealed that citrate-stabilized AuNRs with great biocompatibility could regulate the osteogenic differentiation of multiple cell types through Wnt/ß-catenin signaling pathway, which promote innovative AuNRs in the field of tissue engineering and other biomedical applications.


Asunto(s)
Diferenciación Celular/efectos de los fármacos , Ácido Cítrico/farmacología , Oro/farmacología , Nanotubos/química , Osteogénesis/efectos de los fármacos , Fosfatasa Alcalina/metabolismo , Animales , Calcificación Fisiológica/efectos de los fármacos , Células Cultivadas , Cetrimonio/farmacología , Endocitosis/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/efectos de los fármacos , Ratones , Nanotubos/ultraestructura , Osteogénesis/genética , Ligamento Periodontal/citología , Ratas , Tiazolidinas/farmacología , Vía de Señalización Wnt/efectos de los fármacos
4.
J Chromatogr A ; 1642: 462003, 2021 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-33652369

RESUMEN

To improve extraction performance of carbon fibers (CFs) towards phthalate esters (PAEs), titanium dioxide (TiO2) nanorods array was in-situ grown on the surface of CFs, then polyaniline (PANI) was used to modify it. PANI/TiO2 nanorods-CFs were placed into a polyetheretherketone tube for solid-phase microextraction (SPME). Combining the tube to high performance liquid chromatography (HPLC), it was evaluated and displayed good extraction performance for several PAEs. Compared with bare CFs, TiO2 nanorods and PANI, PANI/TiO2 nanorods presented best performance, attributed to the unique advantages between high surface area of TiO2 nanorods and multiple adsorption interactions (like π-π stacking, hydrogen bond) of PANI. After the optimization of the important factors (sampling volume, sampling rate, sample pH, concentrations of organic solvent and salt in sample, and desorption time), the online in-tube SPME-HPLC method was established. It provided low limits of detection (0.01-0.05 µg L-1) and wide linear ranges (0.03-30, 0.10-30, 0.17-30 µg L-1) with correlation coefficients larger than 0.9991. The relative standard deviations (n=6) between intra-day and inter-day tests were in the ranges of 3.5-10.3% and 4.7-13.9%, respectively. The method was successfully used to determine seven PAEs in real water samples. Besides of satisfactory durability, the material also exhibited superior extraction performance than some materials.


Asunto(s)
Compuestos de Anilina/química , Fibra de Carbono/química , Cromatografía Líquida de Alta Presión/métodos , Ésteres/análisis , Nanotubos/química , Ácidos Ftálicos/análisis , Microextracción en Fase Sólida/métodos , Titanio/química , Adsorción , Cromatografía Líquida de Alta Presión/instrumentación , Cetonas , Espectroscopía de Fotoelectrones , Polietilenglicoles , Reproducibilidad de los Resultados , Solventes/química
5.
J Vis Exp ; (169)2021 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-33749684

RESUMEN

Analyzing the diffusional dynamics of nanoparticles on cell membrane plays a significant role in better understanding the cellular uptake process and provides a theoretical basis for the rational design of nano-medicine delivery. Single particle tracking (SPT) analysis could probe the position and orientation of individual nanoparticles on cell membrane, and reveal their translational and rotational states. Here, we show how to use traditional dark-field microscopy to monitor the dynamics of gold nanorods (AuNRs) on live cell membrane. We also show how to extract the location and orientation of AuNRs using ImageJ and MATLAB, and how to characterize the diffusive states of AuNRs. Statistical analysis of hundreds of particles show that single AuNRs perform Brownian motion on the surface of U87 MG cell membrane. However, individual long trajectory analysis shows that AuNRs have two distinctly different types of motion states on the membrane, namely long-range transport and limited-area confinement. Our SPT methods can be potentially used to study the surface or intracellular particle diffusion in different biological cells and can become a powerful tool for investigations of complex cellular mechanisms.


Asunto(s)
Membrana Celular/química , Oro/química , Microscopía/métodos , Nanopartículas/química , Nanotubos/química , Línea Celular Tumoral , Cetrimonio/química , Análisis de Datos , Difusión , Humanos , Imagen Individual de Molécula , Factores de Tiempo
6.
Molecules ; 26(5)2021 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-33670890

RESUMEN

Prostate cancer is one of the most common cancers in men. Cell invasion is an important step in the process of cancer metastasis. Herein, gold nanorods (GNRs) and polyethylene glycol (PEG)-coated GNRs were conjugated with polydopamine (PDA). The PDA-nanoconjugates demonstrated excellent colloidal stability upon lyophilization and dispersion in cell culture media with or without the addition of fetal bovine albumin (FBS), compared to unconjugated GNRs. PDA-nanoconjugates exhibited a considerable cytotoxicity against DU-145 and PC3 prostate cancer cell lines over a concentration range of 48 µg/mL-12 µg/mL, while they were biocompatible over a concentration range of 3.0 µg/mL-0.185 µg/mL. Furthermore, PDA-nanoconjugates demonstrated possible anti-invasion activity towards prostate cancer cell lines, particularly DU-145 cell line, by reducing cell migration and cell adhesion properties. The PDA-nanoconjugates could be considered a promising nano-platform toward cancer treatment by reducing the invasion activity; it could also be considered a drug delivery system for chemotherapeutic agents.


Asunto(s)
Antineoplásicos/química , Oro/química , Indoles/química , Nanoconjugados/química , Nanotubos/química , Polímeros/química , Neoplasias de la Próstata/tratamiento farmacológico , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Materiales Biocompatibles/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Humanos , Masculino , Polietilenglicoles/química , Propiedades de Superficie
7.
Molecules ; 26(4)2021 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-33669712

RESUMEN

Hydroxyapatite (HA) is the main inorganic mineral that constitutes bone matrix and represents the most used biomaterial for bone regeneration. Over the years, it has been demonstrated that HA exhibits good biocompatibility, osteoconductivity, and osteoinductivity both in vitro and in vivo, and can be prepared by synthetic and natural sources via easy fabrication strategies. However, its low antibacterial property and its fragile nature restricts its usage for bone graft applications. In this study we functionalized a MgHA scaffold with gold nanorods (AuNRs) and evaluated its antibacterial effect against S. aureus and E. coli in both suspension and adhesion and its cytotoxicity over time (1 to 24 days). Results show that the AuNRs nano-functionalization improves the antibacterial activity with 100% bacterial reduction after 24 h. The toxicity study, however, indicates a 4.38-fold cell number decrease at 24 days. Although further optimization on nano-functionalization process are needed for cytotoxicity, these data indicated that Au-NRs nano-functionalization is a very promising method for improving the antibacterial properties of HA.


Asunto(s)
Antiinfecciosos/farmacología , Durapatita/farmacología , Oro/farmacología , Magnesio/farmacología , Nanotubos/química , Muerte Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Nanotubos/ultraestructura , Espectroscopía de Fotoelectrones , Staphylococcus aureus/efectos de los fármacos , Andamios del Tejido/química
8.
Molecules ; 26(4)2021 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-33670610

RESUMEN

This paper presents a facile and low-cost strategy for fabrication lysozyme-loaded mesoporous silica nanotubes (MSNTs) by using silk fibroin (SF) nanofiber templates. The "top-down method" was adopted to dissolve degummed silk in CaCl2/ formic acid (FA) solvent, and the solution containing SF nanofibrils was used for electrospinning to prepare SF nanofiber templates. As SF contains a large number of -OH, -NH2 and -COOH groups, the silica layer could be easily formed on its surface by the Söber sol-gel method without adding any surfactant or coupling agent. After calcination, the MSNTs were obtained with inner diameters about 200 nm, the wall thickness ranges from 37 ± 2 nm to 66 ± 3 nm and the Brunauer-Emmett-Teller (BET) specific surface area was up to 200.48 m2/g, the pore volume was 1.109 cm3/g. By loading lysozyme, the MSNTs exhibited relatively high drug encapsulation efficiency up to 31.82% and an excellent long-term sustained release in 360 h (15 days). These results suggest that the MSNTs with the hierarchical structure of mesoporous and macroporous will be a promising carrier for applications in biomacromolecular drug delivery systems.


Asunto(s)
Fibroínas/química , Muramidasa/metabolismo , Nanofibras/química , Nanotubos/química , Dióxido de Silicio/química , Cloruro de Calcio/química , Liberación de Fármacos , Formiatos/química , Nanofibras/ultraestructura , Nanotubos/ultraestructura , Porosidad , Silanos/química , Soluciones , Espectrometría por Rayos X , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , Termogravimetría , Viscosidad
9.
Int J Nanomedicine ; 16: 1725-1741, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33688188

RESUMEN

Purpose: This study systematically investigated the potential of four model drugs (verapamil HCl, flurbiprofen, atenolol, and furosemide), each belonging to a different class of Biopharmaceutics Classification Systems (BCS) to be developed into oral modified release dosage forms after loading with halloysite nanotubes (HNTs). Methods: The drugs were studied for their loading (mass gain %) by varying solvent system, method, pH, and ratios of loading into the nanotubes using D-optimal split-plot design with the help of Design Expert software. Drug-loaded halloysites were characterized by XRD, DTA, FTIR, SEM, and HPLC-UV-based assay procedures. Dissolution studies were also performed in dissolution media with pH 1.2, 4.5, and 6.8. Moreover, the optimized samples were evaluated under stress stability conditions for determining prospects for the development of oral dosage forms. Results: As confirmed with the results of XRD and DTA, the drugs were found to be converted into amorphous form after loading with halloysite (HNTs). The drugs were loaded in the range of ~7-9% for the four drugs, with agitation providing satisfactory and equivalent loading as compared to vacuum plus agitation based reported methods. FTIR results revealed either only weak electrostatic (verapamil HCl and flurbiprofen) or no interaction with the surface structure of the HNTs. The dissolution profiling depicted significantly retarded release of drugs with Fickian diffusion from a polydisperse system as a model that suits well for the development of oral dosage forms. HPLC-UV-based assay indicated that except furosemide (BCS class IV), the other three drugs are quite suitable for development for oral dosage forms. Conclusion: The four drugs investigated undergo phase transformation with HNTs. While agitation is an optimum method for loading drugs with various physicochemical attributes into HNTs; solvent system, loading ratios and pH play an important role in the loading efficiency respective to the drug properties. The study supports the capability of developing HNT-based modified release oral dosage forms for drugs with high solubility.


Asunto(s)
Biofarmacia/clasificación , Arcilla/química , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Nanotubos/química , Preparaciones Farmacéuticas/administración & dosificación , Administración Oral , Silicatos de Aluminio/química , Cinética , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
10.
Int J Nanomedicine ; 16: 1837-1847, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33692624

RESUMEN

Introduction: Nanotube-based drug delivery systems have received considerable attention because of their large internal volume to encapsulate the drug and the ability to penetrate tissues, cells, and bacteria. In this regard, understanding the interaction between the drug and the nanotube to evaluate the encapsulation behavior of the drug in the nanotube is of crucial importance. Methods: In this work, the encapsulation process of the cationic antimicrobial peptide named cRW3 in the biocompatible boron nitride nanotube (BNNT) was investigated under the Canonical ensemble (NVT) by molecular dynamics (MD) simulation. Results: The peptide was absorbed into the BNNT by van der Waals (vdW) interaction between cRW3 and the BNNT, in which the vdW interaction decreased during the simulation process and reached the value of -142.7 kcal·mol-1 at 4 ns. Discussion: The increase in the potential mean force profile of the encapsulated peptide during the pulling process of cRW3 out of the nanotube showed that its insertion into the BNNT occurred spontaneously and that the inserted peptide had the desired stability. The energy barrier at the entrance of the BNNT caused a pause of 0.45 ns when half of the peptide was inside the BNNT during the encapsulation process. Therefore, during this period, the peptide experienced the weakest movement and the smallest conformational changes.


Asunto(s)
Compuestos de Boro/química , Portadores de Fármacos/química , Nanotubos/química , Proteínas Citotóxicas Formadoras de Poros/farmacología , Aminoácidos/química , Sistemas de Liberación de Medicamentos , Simulación de Dinámica Molecular , Proteínas Citotóxicas Formadoras de Poros/química , Conformación Proteica , Termodinámica
11.
Int J Nanomedicine ; 16: 2219-2236, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33762822

RESUMEN

Introduction: In this paper, we have designed and formulated, a novel synthesis of doxorubicin (DOX) loaded bimetallic gold nanorods in which gold salt (HAuCl4) is chelated with anthracycline (DOX), diacid polyethylene-glycol (PEG-COOH) and gadolinium salt (GdCl3 * 6 H2O) to form DOX IN-Gd-AuNRs compared with DOX ON-Gd-AuNRs in which the drug was grafted onto the bimetallic pegylated nanoparticle surface by electrostatic adsorption. Material and Method: The physical and chemical evaluation was performed by spectroscopic analytical techniques (Raman spectroscopy, UV-Visible and transmission electron microscopy (TEM)). Magnetic features at 7T were also measured. Photothermal abilities were assessed. Cytotoxicity studies on MIA PaCa-2, human pancreatic carcinoma and TIB-75 hepatocytes cell lines were carried out to evaluate their biocompatibility and showed a 320 fold higher efficiency for DOX after encapsulation. Results: Exhaustive physicochemical characterization studies were conducted showing a mid size of 20 to 40 nm diameters obtained with low polydispersity, efficient synthesis using seed mediated synthesis with chelation reaction with high scale-up, long duration stability, specific doxorubicin release with acidic pH, strong photothermal abilities at 808 nm in the NIR transparency window, strong magnetic r1 relaxivities for positive MRI, well adapted for image guided therapy and therapeutical purpose in biological tissues. Conclusion: In this paper, we have developed a novel theranostic nanoparticle composed of gadolinium complexes to gold ions, with a PEG biopolymer matrix conjugated with antitumoral doxorubicin, providing multifunctional therapeutic features. Particularly, these nano conjugates enhanced the cytotoxicity toward tumoral MIAPaCa-2 cells by a factor of 320 compared to doxorubicin alone. Moreover, MRI T1 features at 7T enables interesting positive contrast for bioimaging and their adapted size for potential passive targeting to tumors by Enhanced Permeability Retention. Given these encouraging antitumoral and imaging properties, this bimetallic theranostic nanomaterial system represents a veritable promise as a therapeutic entity in the field of medicinal applications.


Asunto(s)
Doxorrubicina/uso terapéutico , Gadolinio/química , Oro/química , Nanotubos/química , Nanomedicina Teranóstica , Animales , Antibióticos Antineoplásicos/farmacología , Antibióticos Antineoplásicos/uso terapéutico , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Doxorrubicina/farmacología , Liberación de Fármacos , Endocitosis , Humanos , Concentración 50 Inhibidora , Imagen por Resonancia Magnética , Ratones , Nanotubos/ultraestructura , Neoplasias/tratamiento farmacológico , Espectrofotometría Ultravioleta
12.
Int J Nanomedicine ; 16: 2237-2246, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33762823

RESUMEN

Background: Translation of nanomedical developments into clinical application is receiving an increasing interest. However, its use for oral squamous cell carcinoma (OSCC) diagnosis remains limited. We present an advanced nanophotonic method for oral cancer detection, based on diffusion reflection (DR) measurements of gold-nanorods bio-conjugated to anti-epidermal growth factor receptor (C-GNRs) specifically attached to OSCC cells. Objective: To investigate in a rat model of oral carcinogenesis the targeting potential of C-GNRs to OSCC by using the DR optical method. Materials and Methods: OSCC was induced by the carcinogen 4-nitroquinoline-N-oxide (4NQO). C-GNRs were introduced locally and systemically and DR measurements were recorded from the surface of the rat tongue following illumination with red laser beam. Rats were divided into experimental and control groups. The results were compared with the histologic diagnosis. Results: A total of 75 Wistar-derived rats were enrolled in the study. Local application did not reveal any statistical results. DR measurements following intravenous injection of C-GNRs revealed a significant increase in light absorption in rats with OSCC compare with rats without cancer (p<0.02, sensitivity 100%, specificity 89%). In addition, absorption of light increased significantly in cases of severe dysplasia and cancer (high risk) compared to rats without cancer and rats with mild dysplasia (low risk) (86% sensitivity and 89% specificity, AUC=0.79). Conclusion: Combining nanotechnology and nanophotonics for in vivo diagnosis of OSCC serves as additional tier in the translation of advanced nanomedical developments into clinical applications. The presented method shows a promising potential of nanophotonics for oral cancer identification, and provides support for the use of C-GNRs as a selective drug delivery.


Asunto(s)
Carcinoma de Células Escamosas/diagnóstico , Detección Precoz del Cáncer , Receptores ErbB/antagonistas & inhibidores , Oro/química , Neoplasias de la Boca/diagnóstico , Nanotubos/química , Animales , Carcinoma de Células Escamosas/patología , Difusión , Receptores ErbB/metabolismo , Masculino , Neoplasias de la Boca/tratamiento farmacológico , Ratas Wistar
13.
Int J Nanomedicine ; 16: 667-682, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33531806

RESUMEN

Background: Nanostructured surface modifications of Ti-based biomaterials are moving up from a highly-promising to a successfully-implemented approach to developing safe and reliable implants. Methods: The study's main objective is to help consolidate the knowledge and identify the more suitable experimental strategies related to TiO2 nanotubes-modified surfaces. In this sense, it proposes the thorough investigation of two optimized nanotubes morphologies in terms of their biological activity (cell cytotoxicity, alkaline phosphatase activity, alizarin red mineralization test, and cellular adhesion) and their electrochemical behavior in simulated body fluid (SBF) electrolyte. Layers of small-short and large-long nanotubes were prepared and investigated in their amorphous and crystallized states and compared to non-anodized samples. Results: Results show that much more than the surface area development associated with the nanotubes' growth; it is the heat treatment-induced change from amorphous to crystalline anatase-rutile structures that ensure enhanced biological activity coupled to high corrosion resistance. Conclusion: Compared to both non-anodized and amorphous nanotubes layers, the crystallized nano-structures' outstanding bioactivity was related to the remarkable increase in their hydrophilic behavior, while the enhanced electrochemical stability was ascribed to the thickening of the dense rutile barrier layer at the Ti surface beneath the nanotubes.


Asunto(s)
Nanotubos/química , Prótesis e Implantes , Titanio/química , Fosfatasa Alcalina/metabolismo , Adhesión Celular , Línea Celular Tumoral , Supervivencia Celular , Corrosión , Electroquímica , Electrólitos/química , Humanos , Nanotubos/ultraestructura , Humectabilidad
14.
Life Sci ; 270: 119126, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33508295

RESUMEN

AIMS: To investigate the biomimetic fabrication of fibrous-like organic-inorganic hybrid structures via a simple bottom-up approach, viz. self-assembly of simple molecules, and apply fibrous-like composites as a novel primer to improve dentin bond strengths of self-etch adhesives. MATERIALS AND METHODS: The resultants of commercial amorphous calcium phosphate (ACP) nanoparticles and 10-methacryloyloxydecyl dihydrogen phosphate (MDP) ethanol-aqueous solution were analyzed by TEM, SEM, XRD, DLS and AFM. The acid and alkali resistance of abovementioned self-assembled composites were analyzed with TEM. Micro-tensile bond strengths (MTBS) tests were performed after polished dentin surfaces were pretreated with self-assembled composites. The pretreated dentin surfaces and dentin-resin interfaces were characterized by SEM/TEM. KEY FINDINGS: ACP nanoparticles in MDP solution could self-assemble into fibrous-like nanotube structures in 8 nm diameter. Self-assembly and self-proliferation process went from ACP nanoparticles, dissolved ACP nanoparticles (less than 50 nm), twig-like structures and fibrous-like nanotubes to cellular networks. The fibrous-like nanotubes were only detected when the amount of ACP in reaction system were more than 0.01 g. The more ACP interacted with MDP, the more fibrous-like nanotubes were formed. After the dentin surfaces were treated with fibrous-like nanotube composites, MTBS could be significantly improved. Moreover, the fibrous-like nanotube structures could be resistant to acidic challenge, and were stable at least for 3 months. SIGNIFICANCE: The fibrous-like nanotube structures could be self-assembled via a bottom-up approach at certain ratio of MDP and commercial ACP nanoparticles. The application of fibrous-like nanotube composites as a novel primer prior to self-etch adhesives greatly improved dentin bond strengths.


Asunto(s)
Biomimética/métodos , Dentina/química , Nanotubos/química , Adhesivos/química , Fosfatos de Calcio/química , Humanos , Ensayo de Materiales/métodos , Metacrilatos/química , Nanopartículas/química , Resistencia a la Tracción/fisiología
15.
ACS Appl Mater Interfaces ; 13(4): 5678-5690, 2021 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-33492946

RESUMEN

The COVID-19 pandemic has clearly shown the importance of developments in fabrication of advanced protective equipment. This study investigates the potential of using multifunctional electrospun poly(methyl methacrylate) (PMMA) nanofibers decorated with ZnO nanorods and Ag nanoparticles (PMMA/ZnO-Ag NFs) in protective mats. Herein, the PMMA/ZnO-Ag NFs with an average diameter of 450 nm were simply prepared on a nonwoven fabric by directly electrospinning from solutions containing PMMA, ZnO nanorods, and Ag nanoparticles. The novel material showed high performance with four functionalities (i) antibacterial agent for killing of Gram-negative and Gram-positive bacteria, (ii) antiviral agent for inhibition of corona and influenza viruses, (iii) photocatalyst for degradation of organic pollutants, enabling a self-cleaning protective mat, and (iv) reusable surface-enhanced Raman scattering substrate for quantitative analysis of trace pollutants on the nanofiber. This multi-functional material has high potential for use in protective clothing applications by providing passive and active protection pathways together with sensing capabilities.


Asunto(s)
Antiinfecciosos/química , Nanopartículas del Metal/química , Plata/química , Óxido de Zinc/química , Antibacterianos/química , Antivirales/química , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Nanofibras/química , Nanotubos/química , Polimetil Metacrilato/química , Espectrometría Raman
16.
ACS Appl Mater Interfaces ; 13(3): 3653-3668, 2021 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-33439005

RESUMEN

A thin layer of gold nanoparticles (Au NPs) sputtered on cadmium sulfide quantum dots (CdS QDs) decorated anodic titanium dioxide nanotubes (TNTs) (Au/CdS QDs/TNTs) was fabricated and explored for the nonenzymatic detection of cholesterol and hydrogen peroxide (H2O2). Morphological studies of the sensor revealed the formation of uniform nanotubes decorated with a homogeneously dispersed CdS QDs and Au NPs layer. The electrochemical measurements showed an enhanced electrocatalytic performance with a fast electron transfer (∼2 s) between the redox centers of each analyte and electrode surface. The hybrid nanostructure (Au/CdS QDs/TNTs) electrode exhibited about a 6-fold increase in sensitivity for both cholesterol (10,790 µA mM-1 cm-2) and H2O2 (78,833 µA mM-1 cm-2) in analyses compared to the pristine samples. The hybrid electrode utilized different operational potentials for both analytes, which may lead to a voltage-switchable dual-analyte biosensor with a higher selectivity. The biosensor also demonstrated a good reproducibility, thermal stability, and increased shelf life. In addition, the clinical significance of the biosensor was tested for cholesterol and H2O2 in real blood samples, which showed maximum relative standard deviations of 1.8 and 2.3%, respectively. These results indicate that a Au/CdS QDs/TNTs-based hybrid nanostructure is a promising choice for an enzyme-free biosensor due to its suitable band gap alignment and higher electrocatalytic activities.


Asunto(s)
Técnicas Biosensibles/métodos , Colesterol/sangre , Oro/química , Peróxido de Hidrógeno/sangre , Nanopartículas del Metal/química , Compuestos de Cadmio/química , Técnicas Electroquímicas/métodos , Humanos , Límite de Detección , Nanotubos/química , Puntos Cuánticos/química , Sulfuros/química , Titanio/química
17.
ACS Appl Mater Interfaces ; 13(4): 5795-5802, 2021 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-33480669

RESUMEN

A novel ratiometric electrochemical (EC) sensing platform was established for sensitive immunoassay of target cytokeratin 19 fragment 21-1 (CYFRA21-1) biomarker by combining competitive immunoreaction and multisignal output. This immunosensor utilized Ag nanoparticles (NPs)-functionalized urchin-like Fe3O4@polydopamine (u-Fe3O4@PDA-Ag) as a matrix to immobilize CYFRA21-1 antigens and methylene blue (MB)-absorbed Ni3Si2O5(OH)4-Au nanotubes (NTs) to label the anti-CYFRA21-1 (Ab). During the competitive immunoreaction, square wave voltammetric (SWV) current changes of Ag NPs from u-Fe3O4@PDA-Ag indicator and MB from Ni3Si2O5(OH)4-Au/MB indicator are relevant to the dosage of CYFRA21-1-acquired Ni3Si2O5(OH)4-Au/MB/Ab. More importantly, numerous CYFRA21-1 loaded stably on u-Fe3O4@PDA-Ag exhibited strong competitive capacity toward the target-CYFRA21-1 to combine Ni3Si2O5(OH)4-Au/MB/Ab, causing sensitive changes in the ratio of two measured SWV currents. Prominently, "ΔI = ΔIMB + |ΔIAg NPs|" (ΔIMB and |ΔIAg NPs| represents the change values of the oxidation peak currents of MB and Ag NPs, respectively) could be regarded as significantly amplifying the signal response and ultimately improving the sensitivity of CYFRA21-1 detection, from which we derived a wide dynamic range from 500 fg/mL to 50 ng/mL and a low detection limit of 0.39 pg/mL (S/N = 3). This work may exert a profound impact on monitoring other biomarkers in early diagnosis of diseases.


Asunto(s)
Antígenos de Neoplasias/sangre , Óxido Ferrosoférrico/química , Oro/química , Queratina-19/sangre , Azul de Metileno/química , Nanotubos/química , Antígenos de Neoplasias/análisis , Técnicas Electroquímicas/métodos , Humanos , Inmunoensayo/métodos , Indoles/química , Queratina-19/análisis , Límite de Detección , Nanopartículas del Metal/química , Nanopartículas del Metal/ultraestructura , Nanotubos/ultraestructura , Polímeros/química , Compuestos de Silicona/química , Plata/química
18.
J Mater Chem B ; 9(4): 1123-1130, 2021 01 28.
Artículo en Inglés | MEDLINE | ID: mdl-33427845

RESUMEN

Antibiotic contaminants in aqueous media pose a serious threat to human and ecological environments. Therefore, it is necessary to develop robust strategies to detect antibiotic residues. For this purpose, a self-assembly and in situ electrochemical reduction method is utilized to tailor silver nanoparticles (AgNPs)-coated GNRs (AgNPs/GNRs) large-scale vertical arrays. These AgNPs/GNRs arrays exhibit outstanding surface-enhanced Raman scattering (SERS) activities because of abundant Raman hot-spots among the adjacent AgNPs and GNRs, but also excellent stability and reproducibility due to the close-packed arrayed nanostructure. These remarkable features validate this arrayed substrate for high-sensitivity 4-aminothiophenol analysis with a detection limit of 0.35 pM and self-cleaning via electrochemical stripping of the adsorbed analytes and AgNPs from the GNRs arrays, therefore realizing renewable SERS applications. Moreover, the distinct SERS performance of AgNPs/GNRs arrays is verified via the analysis of multiplexed antibiotics at tens of picomolar level and no apparent changes of SERS activities are observed when recyclability is explored. The result demonstrates that the proposed AgNPs/GNRs arrays provide a novel strategy for avoiding conventional, disposable SERS substrates, as well as expanding SERS applications for simultaneous sensing and stripping of environmental contaminants.


Asunto(s)
Compuestos de Anilina/análisis , Antibacterianos/análisis , Oro/química , Nanotubos/química , Plata/química , Compuestos de Sulfhidrilo/análisis , Estructura Molecular , Tamaño de la Partícula , Espectrometría Raman , Propiedades de Superficie
19.
Carbohydr Polym ; 251: 117079, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33142622

RESUMEN

In this study, a surface modification strategy using natural biopolymers on titanium is proposed to improve bone healing and promote rapid and successful osseointegration of orthopedic implants. Titania nanotubes were fabricated via an anodization process and the surfaces were further modified with polyelectrolyte multilayers (PEMs) based on Tanfloc (a cationic tannin derivative) and glycosaminoglycans (heparin and hyaluronic acid). Scanning electron microscopy (SEM), water contact angle measurements, and X-ray photoelectron spectroscopy were used to characterize the surfaces. Adipose-derived stem cells (ADSCs) were seeded on the surfaces, and the cell viability, adhesion, and proliferation were investigated. Osteogenesis was induced and osteogenic differentiation of human ADSCs on the surfaces was evaluated via mineralization and protein expression assays, immunofluorescent staining, and SEM. The Tanfloc/heparin PEMs on titania nanotubes improved the rate of osteogenic differentiation of ADSCs as well as the bone mineral deposition, and is therefore a promising approach for use in orthopedic implants.


Asunto(s)
Tejido Adiposo/citología , Heparina/química , Nanotubos/química , Polielectrolitos/química , Células Madre/citología , Taninos/química , Titanio/química , Tejido Adiposo/efectos de los fármacos , Tejido Adiposo/metabolismo , Anticoagulantes/química , Anticoagulantes/farmacología , Adhesión Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Heparina/farmacología , Humanos , Ácido Hialurónico/química , Osteogénesis , Polielectrolitos/farmacología , Células Madre/efectos de los fármacos , Células Madre/metabolismo , Propiedades de Superficie , Taninos/farmacología
20.
Carbohydr Polym ; 254: 117465, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33357924

RESUMEN

Designing multifunctional surfaces is key to develop advanced materials for orthopedic applications. In this study, we design a double-layer coating, assembled onto the completely regular titania nanotubes (cRTNT) array. Benefiting from the biological and topological characteristics of chitosan nanofibers (CH) and reduced graphene oxide (RGO) through a unique assembly, the designed material features promoted osteoblast cell viability, prolonged antibiotic release profile, as well as inhibited bacterial biofilm formation. The synergistic effect of RGO and CH on the biological performance of the surface is investigatSed. The unique morphology of the nanofibers leads to the partial coverage of RGO-modified nanotubes, providing an opportunity to access the sublayer properties. Another merit of this coating lies in its morphological similarity to the extracellular matrix (ECM) to boost cellular performance. According to the results of this study, this platform holds promising advantages over the bare and bulk biopolymer-modified TNTs.


Asunto(s)
Quitosano/síntesis química , Materiales Biocompatibles Revestidos/química , Grafito/química , Nanocompuestos/química , Osteoblastos/efectos de los fármacos , Titanio/química , Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Adhesión Celular/efectos de los fármacos , Línea Celular , Supervivencia Celular/efectos de los fármacos , Materiales Biocompatibles Revestidos/farmacología , Portadores de Fármacos , Liberación de Fármacos , Humanos , Cinética , Nanocompuestos/ultraestructura , Nanotubos/química , Nanotubos/ultraestructura , Osteoblastos/citología , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo , Vancomicina/farmacología
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