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1.
Int J Nanomedicine ; 16: 4277-4288, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34194228

RESUMO

Introduction: Antimicrobial peptides are potential therapeutics as anti-bacteria, anti-viruses, anti-fungi, or anticancers. However, they suffer from a short half-life and drug resistance which limit their long-term clinical usage. Methods: Herein, we captured the encapsulation of antimicrobial peptide HA-FD-13 into boron nitride nanotube (BNNT) (20,20) and its release due to subsequent insertion of BNNT (14,14) with molecular dynamics simulation. Results: The peptide-BNNT (20,20) van der Waals (vdW) interaction energy decreased to -270 kcal·mol-1 at the end of the simulation (15 ns). However, during the period of 0.2-1.8 ns, when half of the peptide was inside the nanotube, the encapsulation was paused due to an energy barrier in the vicinity of BNNT and subsequently the external intervention, such that the self-adjustment of the peptide allowed full insertion. The free energy of the encapsulation process was -200.12 kcal·mol-1, suggesting that the insertion procedure occurred spontaneously. Discussion: Once the BNNT (14,14) entered into the BNNT (20,20), the peptide was completely released after 83.8 ps. This revealed that the vdW interaction between the BNNT (14,14) and BNNT (20,20) was stronger than between BNNT (20,20) and the peptide; therefore, the BNNT (14,14) could act as a piston pushing the peptide outside the BNNT (20,20). Moreover, the sudden drop in the vdW energy between nanotubes to the value of the -1300 Kcal·mol-1 confirmed the self-insertion of the BNNT (14,14) into the BNNT (20,20) and correspondingly the release of the peptide.


Assuntos
Compostos de Boro/química , Nanotubos/química , Proteínas Citotóxicas Formadoras de Poros/química , Proteínas Citotóxicas Formadoras de Poros/farmacocinética , Simulação de Dinâmica Molecular , Conformação Proteica em alfa-Hélice
2.
Nat Commun ; 12(1): 3557, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-34117248

RESUMO

Bottom-up synthetic biology aims to engineer artificial cells capable of responsive behaviors by using a minimal set of molecular components. An important challenge toward this goal is the development of programmable biomaterials that can provide active spatial organization in cell-sized compartments. Here, we demonstrate the dynamic self-assembly of nucleic acid (NA) nanotubes inside water-in-oil droplets. We develop methods to encapsulate and assemble different types of DNA nanotubes from programmable DNA monomers, and demonstrate temporal control of assembly via designed pathways of RNA production and degradation. We examine the dynamic response of encapsulated nanotube assembly and disassembly with the support of statistical analysis of droplet images. Our study provides a toolkit of methods and components to build increasingly complex and functional NA materials to mimic life-like functions in synthetic cells.


Assuntos
DNA/química , Nanotecnologia/métodos , Nanotubos/química , Células Artificiais , Materiais Biocompatíveis , Emulsões , Gotículas Lipídicas , Substâncias Macromoleculares , Modelos Moleculares , Conformação de Ácido Nucleico , Oligonucleotídeos , Biologia Sintética , Água
3.
Food Chem ; 362: 130261, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34111691

RESUMO

In this study, a novel surface enhanced Raman spectroscopy (SERS) sensor was developed for the ultrasensitive determination of kanamycin in foods. The sensor used two distinct signal amplification strategies, namely the surface plasmon resonance of gold nanorods and a Zn-doped carbon quantum dots catalytic cascade oxidation-reduction reaction switch controlled by a nucleic acid aptamer. Under optimized experimental conditions, the SERS sensor demonstrated a linear range of 10-12 to 10-5 g mL-1 for the detection of kanamycin, with a limit of detection of 3.03 × 10-13 g mL-1. Experiments with antibiotics structurally similar to kanamycin and interferrants revealed that the sensor had excellent selectivity. Milkpowder and honey samples spiked with kanamycin were assayed, with recoveries ranging from 84.1% to 107.2% and a relative standard deviation of 0.74% to 2.81% being obtained. Quantification of kanamycin in milk samples revealed no significant difference between the results obtained with the sensor and by HPLC.


Assuntos
Aptâmeros de Nucleotídeos/química , Análise de Alimentos/instrumentação , Análise de Alimentos/métodos , Canamicina/análise , Nanotubos/química , Pontos Quânticos/química , Zinco/química , Antibacterianos/análise , Técnicas Biossensoriais/instrumentação , Carbono/química , Catálise , Ouro/química , Limite de Detecção , Nanopartículas Metálicas/química , Análise Espectral Raman/métodos , Ressonância de Plasmônio de Superfície
4.
Int J Nanomedicine ; 16: 3407-3427, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34040371

RESUMO

Purpose: Plasmonic photothermal cancer therapy by gold nanorods (GNRs) emerges as a promising tool for cancer treatment. The goal of this study was to design cationic oligoethylene glycol (OEG) compounds varying in hydrophobicity and molecular electrostatic potential as ligand shells of GNRs. Three series of ligands with different length of OEG chain (ethylene glycol units = 3, 4, 5) and variants of quaternary ammonium salts (QAS) as terminal functional group were synthesized and compared to a prototypical quaternary ammonium ligand with alkyl chain - (16-mercaptohexadecyl)trimethylammonium bromide (MTAB). Methods: Step-by-step research approach starting with the preparation of compounds characterized by NMR and HRMS spectra, GNRs ligand exchange evaluation through characterization of cytotoxicity and GNRs cellular uptake was used. A method quantifying the reshaping of GNRs was applied to determine the effect of ligand structure on the heat transport from GNRs under fs-laser irradiation. Results: Fourteen out of 18 synthesized OEG compounds successfully stabilized GNRs in the water. The colloidal stability of prepared GNRs in the cell culture medium decreased with the number of OEG units. In contrast, the cellular uptake of OEG+GNRs by HeLa cells increased with the length of OEG chain while the structure of the QAS group showed a minor role. Compared to MTAB, more hydrophilic OEG compounds exhibited nearly two order of magnitude lower cytotoxicity in free state and provided efficient cellular uptake of GNRs close to the level of MTAB. Regarding photothermal properties, OEG compounds evoked the photothermal reshaping of GNRs at lower peak fluence (14.8 mJ/cm2) of femtosecond laser irradiation than the alkanethiol MTAB. Conclusion: OEG+GNRs appear to be optimal for clinical applications with systemic administration of NPs not-requiring irradiation at high laser intensity such as drug delivery and photothermal therapy inducing apoptosis.


Assuntos
Ouro/química , Ouro/metabolismo , Nanotubos/química , Polietilenoglicóis/química , Compostos de Amônio Quaternário/química , Temperatura , Transporte Biológico , Coloides , Estabilidade de Medicamentos , Células HeLa , Humanos , Interações Hidrofóbicas e Hidrofílicas , Ligantes
5.
Nat Commun ; 12(1): 3207, 2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-34050157

RESUMO

In living organisms, proteins are organized prevalently through a self-association mechanism to form dimers and oligomers, which often confer new functions at the intermolecular interfaces. Despite the progress on DNA-assembled artificial systems, endeavors have been largely paid to achieve monomeric nanostructures that mimic motor proteins for a single type of motion. Here, we demonstrate a DNA-assembled building block with rotary and walking modules, which can introduce new motion through dimerization and oligomerization. The building block is a chiral system, comprising two interacting gold nanorods to perform rotation and walking, respectively. Through dimerization, two building blocks can form a dimer to yield coordinated sliding. Further oligomerization leads to higher-order structures, containing alternating rotation and sliding dimer interfaces to impose structural twisting. Our hierarchical assembly scheme offers a design blueprint to construct DNA-assembled advanced architectures with high degrees of freedom to tailor the optical responses and regulate multi-motion on the nanoscale.


Assuntos
DNA de Cadeia Simples/química , Nanotecnologia/métodos , Dicroísmo Circular , Dimerização , Ouro/química , Nanotubos/química
6.
Food Chem ; 359: 129847, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33964656

RESUMO

Surface-enhanced Raman spectroscopy (SERS) and deep learning network were adopted to develop a detection method for deoxynivalenol (DON) residues in Fusarium head blight (FHB)-infected wheat kernels. First, the liquid-liquid interface self-extraction was conducted for the rapid separation of DON in samples. Then, the gold nanorods modified with sodium citrate (Cit-AuNRs) were prepared as substrate for a gigantic enhancement of SERS signal. Results showed that the spectral characteristic peaks for DON residues of 99.5-0.5 mg/L were discernible with the relative standard deviation of 4.2%, with the limit of detection of 0.11 mg/L. Meanwhile, the fully convolutional network for the spectra of matrix input form was developed and obtained the optimal quantitative performance, with a root-mean-square error of prediction of 4.41 mg/L and coefficient of determination of prediction of 0.9827. Thus, the proposed method provides a simple, sensitive, and intelligent detection for DON in FHB-infected wheat kernels.


Assuntos
Fusarium/fisiologia , Ouro/química , Nanotubos/química , Citrato de Sódio/química , Análise Espectral Raman/métodos , Tricotecenos/análise , Triticum/química , Extração Líquido-Líquido , Doenças das Plantas/microbiologia , Tricotecenos/isolamento & purificação , Triticum/microbiologia
7.
Int J Nanomedicine ; 16: 3329-3342, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34012262

RESUMO

Background and Purpose: Micro-/nano-tubes (TNTs) and micro-/nano-nets (TNNs) are the common and sensible choice in the first step of combined modifications of titanium surface for further functionalization in the purpose of extended indications and therapeutic effect. It is important to recognize the respective biologic reactions of these two substrates for guiding a biologically based first-step selection. Materials and Methods: TNTs were produced by anodic oxidation and TNNs were formed by alkali-heat treatment. The original selective laser melting (SLM) titanium surface was set as control. Surface characterization was evaluated by scanning electron microscopy, surface roughness, and water contact angle measurements. Osteoclastogenesis and osteogenesis were measured. MC3T3-E1 cells and RAW 264.7 cells were used for in vitro assay in terms of adhesion, proliferation, and differentiation. In vivo assessments were taken on Beagle dogs with micro-CT and histological analysis. Results: TNN and TNT groups performed decreased roughness and increased hydrophilicity compared with SLM group. For biological detections, the highest ALP activity and osteogenesis-related genes expression were observed in TNT group followed by TNN group (P <0.05). Interestingly, when it comes to the osteoclastogenesis, TNNs displayed lowest TRAP activity and osteoclastogenesis-related genes expression and TNTs were lower than SLM but higher than TNNs (P <0.05). BV/TV around implants was highest in TNT group after 4 weeks (P <0.05). HE, ALP and TRAP staining showed that osteogenic and osteoclastic activity around TNTs were both higher than TNNs (P <0.05). Conclusion: TNNs and TNTs have dual advantages in promotion of osteogenesis and inhibition of osteoclastogenesis. Furthermore, TNNs showed better capability in inhibiting osteoclast activity while TNTs facilitated stronger osteogenesis. Our results implied that TNT substrates would take advantage in early application after implantation, while diseases with inappropriate osteoclast activity would prefer TNN substrates, which will guide a biologically based first-step selection on combined modification for different clinical purposes.


Assuntos
Lasers , Nanotubos/química , Osseointegração/efeitos dos fármacos , Osseointegração/efeitos da radiação , Titânio/farmacologia , Células 3T3 , Animais , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cães , Camundongos , Microscopia Eletrônica de Varredura , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Próteses e Implantes , Células RAW 264.7 , Propriedades de Superfície , Titânio/química
8.
Inorg Chem ; 60(9): 6585-6599, 2021 May 03.
Artigo em Inglês | MEDLINE | ID: covidwho-1195597

RESUMO

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.


Assuntos
Espectroscopia Dielétrica/instrumentação , Espectroscopia Dielétrica/métodos , Levofloxacino/análise , Nanocompostos/química , Antivirais/análise , Antivirais/sangue , Antivirais/urina , Carbono/química , Eletrodos , Grafite/química , Humanos , Levofloxacino/sangue , Levofloxacino/urina , Limite de Detecção , Nanopartículas Metálicas/química , Microscopia Eletrônica de Transmissão , Nanotubos/química , Espectroscopia Fotoeletrônica , Prata/química , Compostos de Prata/química , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Comprimidos , Vanadatos/química , Difração de Raios X
9.
Inorg Chem ; 60(9): 6585-6599, 2021 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-33878862

RESUMO

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.


Assuntos
Espectroscopia Dielétrica/instrumentação , Espectroscopia Dielétrica/métodos , Levofloxacino/análise , Nanocompostos/química , Antivirais/análise , Antivirais/sangue , Antivirais/urina , Carbono/química , Eletrodos , Grafite/química , Humanos , Levofloxacino/sangue , Levofloxacino/urina , Limite de Detecção , Nanopartículas Metálicas/química , Microscopia Eletrônica de Transmissão , Nanotubos/química , Espectroscopia Fotoeletrônica , Prata/química , Compostos de Prata/química , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Comprimidos , Vanadatos/química , Difração de Raios X
10.
Int J Nanomedicine ; 16: 2789-2801, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33880024

RESUMO

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.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Ácido Cítrico/farmacologia , Ouro/farmacologia , Nanotubos/química , Osteogênese/efeitos dos fármacos , Fosfatase Alcalina/metabolismo , Animais , Calcificação Fisiológica/efeitos dos fármacos , Células Cultivadas , Cetrimônio/farmacologia , Endocitose/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos , Nanotubos/ultraestrutura , Osteogênese/genética , Ligamento Periodontal/citologia , Ratos , Tiazolidinas/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos
11.
Nat Commun ; 12(1): 2025, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33795690

RESUMO

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.


Assuntos
Dicroísmo Circular/métodos , DNA/química , Ouro/química , Nanotubos/química , DNA/genética , DNA/ultraestrutura , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Transmissão , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Estereoisomerismo
12.
Inorg Chem ; 60(7): 5264-5270, 2021 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-33719433

RESUMO

Imaging the catalytic activity at the single-particle level can greatly promote the screening and rational design of highly efficient nanozymes, but conventional techniques are based on ensemble analysis. Here, we present a new absorption microscopy for in situ visualizing oxidase-mimicking activity of single MnOOH nanotubes. The particle with a size more than 700 nm roughly equally scatters all wavelengths of visible light via Mie scattering, and the scattering light is collected by dark-field optical microscopy. When the particles absorb a single color of the scattering light, each individual nanoparticle shows its complementary color, enabling a form of absorption microscopy that we name Mie scattering-based absorption microscopy. We find that MnOOH nanotubes can catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) to generate polyTMB nanowires at their tips. There are multiple active sites on the surface of the individual nanotube, and the nanozyme activity shows a large heterogeneity as well as pH-dependent characteristic.


Assuntos
Compostos de Manganês/metabolismo , Nanotubos/química , Concentração de Íons de Hidrogênio , Compostos de Manganês/síntese química , Compostos de Manganês/química , Tamanho da Partícula , Espectrofotometria Ultravioleta , Propriedades de Superfície
13.
ACS Appl Mater Interfaces ; 13(13): 14875-14884, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33759489

RESUMO

Grafting biomolecules on nanostructures' surfaces is an increasingly used strategy to target pathogenic cells, with both diagnostic and therapeutic applications. However, nanomaterials monofunctionalized by conjugating a single type of ligand find limited uses in pathologies/therapies that require two or more targets/receptors to be targeted and/or activated with a single molecular entity simultaneously. Therefore, multivalent nanomaterials for dual- or multitargeting are attracting significant interest. This study provides a proof of concept of such nanostructures. We have recently developed a modular methodology that allows obtaining amyloid-based materials decorated with active globular domains. Here, this approach is exploited to generate functional amyloid fibrils displaying antibody capture moieties. A high antibody binding affinity and capacity for the resulting nanofibrils, whose size can be manipulated to obtain homogeneous nanorods with high biocompatibility, are demonstrated. These nanorods are then used for specific antibody-mediated targeting of different cell types. Simultaneous conjugation of these nanorods with different antibodies allows obtaining a mimic of a bispecific antibody that redirects T lymphocytes to tumoral cells, holding high potential for immunotherapy. Overall, the work illustrates a modular and straightforward strategy to obtain preparative quantities of multivalent antibody-functionalized nanomaterials with multitargeting properties without the need for covalent modification.


Assuntos
Antineoplásicos Imunológicos/farmacologia , Comunicação Celular/efeitos dos fármacos , Imunoconjugados/farmacologia , Nanotubos , Amiloide/química , Amiloide/farmacologia , Anticorpos Biespecíficos/química , Anticorpos Biespecíficos/farmacologia , Antineoplásicos Imunológicos/química , Linhagem Celular Tumoral , Humanos , Imunoconjugados/química , Nanotubos/química , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Termodinâmica
14.
ACS Appl Mater Interfaces ; 13(13): 14974-14984, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33761255

RESUMO

Photoacoustic (PA) imaging holds great promise as a noninvasive imaging modality. Gold nanorods (GNRs) with absorption in the second near-infrared (NIR-II) window have emerged as excellent PA probes because of their tunable optical absorption, surface modifiability, and low toxicity. However, pristine GNRs often undergo shape transition upon laser illumination due to thermodynamic instability, leading to a reduced PA signal after a few seconds of imaging. Here, we report monodisperse GNR-melanin nanohybrids where a tunable polydopamine (PDA) coating was conformally coated on GNRs. GNR@PDAs showed a threefold higher PA signal than pristine GNRs due to the increased optical absorption, cross-sectional area, and thermal confinement. More importantly, the PA signal of GNR@PDAs only decreased by 29% during the 5 min of laser illumination in the NIR-II window, while significant attenuation (77%) was observed for GNRs. The GNR@PDAs maintained 87% of its original PA signal in vivo even after 10 min of laser illumination. This PDA-enabled strategy affords a rational design for robust PA imaging probes and provides more opportunities for other types of photomediated biomedicines, such as photothermal and photodynamic regimens.


Assuntos
Ouro/química , Melaninas/química , Nanotubos/química , Animais , Indóis/química , Raios Infravermelhos , Camundongos , Nanotubos/ultraestrutura , Técnicas Fotoacústicas/métodos , Polímeros/química
15.
ACS Appl Mater Interfaces ; 13(13): 14894-14910, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33769025

RESUMO

Multidrug resistance (MDR) is identified as a major impediment to the efficient chemotherapy of cancer, and considerable endeavors have been devoted to reverse MDR containing structuring varieties of multifunctional nanocarriers. Here, a specially light-activated hollow mesoporous silica nanocontainer with an in situ-synthesized Au nanorod (AuNR) core and a surface-modified hairpin structure DNA gatekeeper is reported for treating MDR tumor cells. In this system, the AuNR only fills part of the space in hollow mesoporous silica due to its controllable size, and the remaining space is used to load enough DOX. By controlling the near-infrared (NIR) laser intensity and exposure duration, the configuration of hairpin-structured DNA (Tm = 51.4 °C) can change reversibly and then trigger the controllable intracellular release of DOX, leading to a significantly enhanced chemotherapeutic efficacy and adjustable photothermal treatment for multidrug-resistant cancer cells. The in vitro experiments showed that this system could effectively overcome the MDR of HepG2-adm cells (a MDR cell line of human hepatocarcinoma cells) by the increased concentration of DOX intracellularly and the photothermal conversion of AuNRs, even at a low concentration (e.g., 30 µg mL-1). Therefore, this NIR-triggered chemo-photothermal synergistic treatment system can be used as a promising efficient strategy in reversing the multidrug resistance for cancer therapy.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Preparações de Ação Retardada/química , Doxorrubicina/administração & dosagem , Ouro/química , Nanotubos/química , Dióxido de Silício/química , Antibióticos Antineoplásicos/farmacologia , Cápsulas , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Células Hep G2 , Humanos , Raios Infravermelhos , Neoplasias/tratamento farmacológico
16.
Int J Nanomedicine ; 16: 1725-1741, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33688188

RESUMO

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.


Assuntos
Biofarmácia/classificação , Argila/química , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Nanotubos/química , Preparações Farmacêuticas/administração & dosagem , Administração Oral , Silicatos de Alumínio/química , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
17.
Int J Nanomedicine ; 16: 1837-1847, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33692624

RESUMO

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.


Assuntos
Compostos de Boro/química , Portadores de Fármacos/química , Nanotubos/química , Proteínas Citotóxicas Formadoras de Poros/farmacologia , Aminoácidos/química , Sistemas de Liberação de Medicamentos , Simulação de Dinâmica Molecular , Proteínas Citotóxicas Formadoras de Poros/química , Conformação Proteica , Termodinâmica
18.
Int J Nanomedicine ; 16: 2219-2236, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33762822

RESUMO

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.


Assuntos
Doxorrubicina/uso terapêutico , Gadolínio/química , Ouro/química , Nanotubos/química , Nanomedicina Teranóstica , Animais , Antibióticos Antineoplásicos/farmacologia , Antibióticos Antineoplásicos/uso terapêutico , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Liberação Controlada de Fármacos , Endocitose , Humanos , Concentração Inibidora 50 , Imageamento por Ressonância Magnética , Camundongos , Nanotubos/ultraestrutura , Neoplasias/tratamento farmacológico , Terapia Fototérmica , Espectrofotometria Ultravioleta
19.
Int J Nanomedicine ; 16: 2237-2246, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33762823

RESUMO

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.


Assuntos
Carcinoma de Células Escamosas/diagnóstico , Detecção Precoce de Câncer , Receptores ErbB/antagonistas & inibidores , Ouro/química , Neoplasias Bucais/diagnóstico , Nanotubos/química , Animais , Carcinoma de Células Escamosas/patologia , Difusão , Receptores ErbB/metabolismo , Masculino , Neoplasias Bucais/tratamento farmacológico , Ratos Wistar
20.
J Chromatogr A ; 1642: 462003, 2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33652369

RESUMO

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.


Assuntos
Compostos de Anilina/química , Fibra de Carbono/química , Cromatografia Líquida de Alta Pressão/métodos , Ésteres/análise , Nanotubos/química , Ácidos Ftálicos/análise , Microextração em Fase Sólida/métodos , Titânio/química , Adsorção , Cromatografia Líquida de Alta Pressão/instrumentação , Cetonas , Espectroscopia Fotoeletrônica , Polietilenoglicóis , Reprodutibilidade dos Testes , Solventes/química
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