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1.
Int J Mol Sci ; 22(12)2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208594

RESUMO

This article describes the synthesis and characterization of ß-cyclodextrin-based nano-sponges (NS) inclusion compounds (IC) with the anti-tumor drugs melphalan (MPH) and cytoxan (CYT), and the addition of gold nanoparticles (AuNPs) onto both systems, for the potential release of the drugs by means of laser irradiation. The NS-MPH and NS-CYT inclusion compounds were characterized using scanning electron microscopy (SEM), X-ray powder diffraction (XRPD), energy dispersive spectroscopy (EDS), thermogravimetric analysis (TGA), UV-Vis, and proton nuclear magnetic resonance (1H-NMR). Thus, the inclusion of MPH and CYT inside the cavities of NSs was confirmed. The association of AuNPs with the ICs was confirmed by SEM, EDS, TEM, and UV-Vis. Drug release studies using NSs synthesized with different molar ratios of ß-cyclodextrin and diphenylcarbonate (1:4 and 1:8) demonstrated that the ability of NSs to entrap and release the drug molecules depends on the crosslinking between the cyclodextrin monomers. Finally, irradiation assays using a continuous laser of 532 nm showed that photothermal drug release of both MPH and CYT from the cavities of NSs via plasmonic heating of AuNPs is possible.


Assuntos
Ciclodextrinas , Ciclofosfamida/administração & dosagem , Portadores de Fármacos , Ouro , Melfalan/administração & dosagem , Nanopartículas Metálicas , Técnicas de Química Sintética , Ciclodextrinas/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos/efeitos da radiação , Ouro/química , Luz , Espectroscopia de Ressonância Magnética , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Temperatura , Termogravimetria , Tocoferóis , Difração de Raios X
2.
Int J Mol Sci ; 22(13)2021 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-34281254

RESUMO

Silver nanoparticles (AgNPs) have been imposed as an excellent antimicrobial agent being able to combat bacteria in vitro and in vivo causing infections. The antibacterial capacity of AgNPs covers Gram-negative and Gram-positive bacteria, including multidrug resistant strains. AgNPs exhibit multiple and simultaneous mechanisms of action and in combination with antibacterial agents as organic compounds or antibiotics it has shown synergistic effect against pathogens bacteria such as Escherichia coli and Staphylococcus aureus. The characteristics of silver nanoparticles make them suitable for their application in medical and healthcare products where they may treat infections or prevent them efficiently. With the urgent need for new efficient antibacterial agents, this review aims to establish factors affecting antibacterial and cytotoxic effects of silver nanoparticles, as well as to expose the advantages of using AgNPs as new antibacterial agents in combination with antibiotic, which will reduce the dosage needed and prevent secondary effects associated to both.


Assuntos
Antibacterianos/uso terapêutico , Nanopartículas Metálicas/uso terapêutico , Prata/uso terapêutico , Animais , Antibacterianos/administração & dosagem , Antibacterianos/química , Infecções Bacterianas/tratamento farmacológico , Linhagem Celular , Desenvolvimento de Medicamentos , Farmacorresistência Bacteriana , Escherichia coli/efeitos dos fármacos , Humanos , Nanopartículas Metálicas/administração & dosagem , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Nanotecnologia , Pseudomonas aeruginosa/efeitos dos fármacos , Prata/administração & dosagem , Prata/química , Staphylococcus aureus/efeitos dos fármacos
3.
Int J Mol Sci ; 21(11)2020 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-32517363

RESUMO

This article describes the use of ß-cyclodextrin-based carbonate nanosponges (NSs) decorated with superparamagnetic Fe3O4 nanoparticles to study and investigate the potential removal of dinotefuran (DTF) from wastewater. The NS-DTF inclusion compound was characterized by transmission electron microscopy (TEM), energy-dispersive spectroscopy (EDS), UV-visible spectroscopy (UV-VIS), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), X-ray powder diffraction (XRPD) and proton nuclear magnetic resonance (1H-NMR). The adsorption efficiency of NSs was evaluated as function of different contact times. The results confirmed that the NSs have a favourable sorption capacity for the chosen guest, as the polymers exhibited a maximum adsorption of 4.53 × 10-3 mmol/g for DTF. We also found that magnetic NSs show good reusability as they maintain their efficiency after eight adsorption and desorption cycles. Our studies and characterization by means of SEM, TEM, EDS, vibrating sample magnetometer (VSM) and UV-VIS also show that NSs with magnetic properties are excellent tools for insecticide removal from aqueous environments.


Assuntos
Guanidinas/química , Nanopartículas de Magnetita/química , Nanocompostos/química , Neonicotinoides/química , Nitrocompostos/química , Águas Residuárias/química , Poluentes Químicos da Água/química , beta-Ciclodextrinas/química , Adsorção , Teoria da Densidade Funcional , Espectroscopia de Ressonância Magnética , Nanopartículas de Magnetita/ultraestrutura , Estrutura Molecular , Nanocompostos/ultraestrutura
4.
Carbohydr Polym ; 233: 115865, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32059912

RESUMO

In this work, we present a solid silicon substrate functionalized with modified ß-cyclodextrin monolayers as an optimal surface for organic contaminant uptake. The inclusion and capture of three potential pollutants, 4-chlorophenoxyacetic acid, 4-aminobenzoic acid and phenylethylamine, were studied. 1H-NMR and ROESY studies revealed the complete inclusion and details of the conformational orientation of the three guests in the per-(6-amino-6-deoxy)-ß-cyclodextrin matrix, forming three new inclusion complexes that have not yet been reported. Capture assays for the guests were carried out by immersing the substrates in an aqueous pollutant solution and by measuring the UV-vis spectra. This substrate showed a high sorption capacity at equilibrium, between 2.5 × 10-5 and 6.0 × 10-5 mmol/substrate, for the studied pollutants. In addition, this surface can be reused four times with an efficiency equal to the initial use. Therefore, it could be a versatile platform that could be applied for the capture of other organic pollutants from water.

5.
Nanomaterials (Basel) ; 8(12)2018 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-30486514

RESUMO

The inclusion compound (IC) of cyclodextrin (CD) containing the antitumor drug Methotrexate (MTX) as a guest molecule was obtained to increase the solubility of MTX and decrease its inherent toxic effects in nonspecific cells. The IC was conjugated with gold nanoparticles (AuNPs), obtained by a chemical method, creating a ternary intelligent delivery system for MTX molecules, based on the plasmonic properties of the AuNPs. Irradiation of the ternary system, with a laser wavelength tunable with the corresponding surface plasmon of AuNPs, causes local energy dissipation, producing the controlled release of the guest from CD cavities. Finally, cell viability was evaluated using MTS assays for ß-CD/MTX and AuNPs + ß-CD/MTX samples, with and without irradiation, against HeLa tumor cells. The irradiated sample of the ternary system AuNPs + ß-CD/MTX produced a diminution in cell viability attributed to the photothermal release of MTX.

6.
Polymers (Basel) ; 10(9)2018 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-30960963

RESUMO

This article describes the sorption properties of cyclodextrin polymers (nanosponges; NS) with the pesticides 4-chlorophenoxyacetic acid (4-CPA) and 2,3,4,6-tetrachlorophenol (TCF), including an evaluation of its efficiency and a comparison with other materials, such as granulated activated carbon (GAC). NS-pesticide complexes were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray powder diffraction (XRPD), proton nuclear magnetic resonance (¹H-NMR), UV⁻VIS, and thermogravimetric analysis (TGA). This confirms the interactions of the guests with nanosponges and shows that the polymers have favorable sorption capacities for chlorinated aromatic guests. Our studies also show that the inclusion complex is predominantly favored for NS/CPA rather than those formed between TCF and NS due to the size of the adsorbate and steric effects. Sorption studies carried with repeated cycles demonstrate that NS polymers could be an improved technology for pollutant removal from aquatic environments, as they are very efficient and reusable materials. Our experiments and characterization by SEM, EDS, UV⁻VIS, and magnetization saturation (VSM) also show that NS is an optimal substrate for the deposition of magnetite nanoparticles, thus improving the usefulness and properties of the polymer, as the nanosponges could be retrieved from aqueous solution with a neodymium magnet without losing its efficiency as a pesticide sorbent.

7.
Molecules ; 21(11)2016 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-27801880

RESUMO

Cyclodextrin (CD) molecules form inclusion compounds (ICs), generating dimers that are capable of encapsulating molecules derived from long-chain hydrocarbons. The aim of this study is to evaluate the structural changes experienced by ICs in solution with increasing temperatures. For this, a nuclear magnetic resonance (¹H-NMR) titration was performed to determinate the stoichiometric α-cyclodextrin (α-CD):octylamine (OA) 2:1 and binding constant (k = 2.16 M-2) of ICs. Solution samples of α-CD-OA ICs conjugated with gold nanoparticles (AuNPs) were prepared, and ¹H-NMR spectra at different temperatures were recorded. Comparatively, ¹H-NMR spectra of the sample irradiated with a laser with tunable wavelengths, with plasmons of conjugated AuNPs, were recorded. In this work, we present evidence of the disassembly of ICs conjugated with AuNPs. Thermal studies demonstrated that, at 114 °C, there are reversible rearrangements of the host and guests in the ICs in a solid state. Migration movements of the guest molecules from the CD cavity were monitored via temperature-dependent ¹H-NMR, and were verified comparing the chemical shifts of octylamine dissolved in deuterated dimethylsulfoxide (DMSO-d6) with the OA molecule included in α-CD dissolved in the same solvent. It was observed that, at 117 °C, OA exited the α-CD cavity. CD IC dimer disassembly was also observed when the sample was irradiated with green laser light.


Assuntos
Aminas/química , Ouro/química , alfa-Ciclodextrinas/química , Liberação Controlada de Fármacos , Temperatura Alta , Nanopartículas Metálicas/química , Microscopia de Força Atômica , Estrutura Molecular
8.
Nanoscale Res Lett ; 11(1): 180, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27053258

RESUMO

Evidence of guest migration in α-cyclodextrin-octylamine (α-CD-OA) inclusion compound (IC) generated via plasmonic heating of gold nanoparticles (AuNPs) has been studied. In this report, we demonstrate local effects generated by laser-mediated irradiation of a sample of AuNPs covered with inclusion compounds on surface-derivatized glass under liquid conditions by atomic force microscopy (AFM). Functionalized AuNPs on the glass and covered by the ICs were monitored by recording images by AFM during 5 h of irradiation, and images showed that after irradiation, a drastic decrease in the height of the AuNPs occurred. The absorption spectrum of the irradiated sample showed a hypsochromic shift from 542 to 536 nm, evidence suggesting that much of the population of nanoparticles lost all of the parts of the overlay of ICs due to the plasmonic heat generated by the irradiation. Mass spectrometry matrix-assisted laser desorption/ionization-time-of-flight (MALDI-TOF) performed on a sample containing a collection of drops obtained from the surface of the functionalized glass provided evidence that the irradiation lead to disintegration of the ICs and therefore exit of the octylamine molecule (the guest) from the cyclodextrin cavity (the matrix). Graphical Abstract Atomic Force Microscopy observation of the disintegration of a cyclodextrin inclusion compound by gold nanoparticles photothermal effect.

9.
ACS Appl Mater Interfaces ; 7(28): 15177-88, 2015 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-26091143

RESUMO

We report the synthesis of a 1:1 ß-cyclodextrin-phenylethylamine (ßCD-PhEA) inclusion complex (IC) and the adhesion of gold nanoparticles (AuNPs) onto microcrystals of this complex, which forms a ternary system. The formation of the IC was confirmed by powder X-ray diffraction and NMR analyses ((1)H and ROESY). The stability constant of the IC (760 M(-1)) was determined using the phase solubility method. The adhesion of AuNPs was obtained using the magnetron sputtering technique, and the presence of AuNPs was confirmed using UV-vis spectroscopy (surface plasmon resonance effect), which showed an absorbance at 533 nm. The powder X-ray diffractograms of ßCD-PhEA were similar to those of the crystals decorated with AuNPs. A comparison of the one- and two-dimensional NMR spectra of the IC with and without AuNPs suggests partial displacement of the guest to the outside of the ßCD due to attraction toward AuNPs, a characteristic tropism effect. The size, morphology, and distribution of the AuNPs were analyzed using TEM and SEM. The average size of the AuNPs was 14 nm. Changes in the IR and Raman spectra were attributed to the formation of the complex and to the specific interactions of this group with the AuNPs. Laser irradiation assays show that the ternary system ßCD-PhEA-AuNPs in solution enables the release of the guest.


Assuntos
Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/instrumentação , Ouro/química , Nanopartículas/química , Fenetilaminas/química , beta-Ciclodextrinas/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos
10.
Am J Physiol Lung Cell Mol Physiol ; 308(6): L511-22, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25575513

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a progressive and usually lethal interstitial lung disease of unknown etiology characterized by aberrant activation of epithelial cells that induce the migration, proliferation and activation of fibroblasts. The resulting distinctive fibroblastic/myofibroblastic foci are responsible for the excessive extracellular matrix (ECM) production and abnormal lung remodeling. We have recently found that matrix metalloproteinase 19 (MMP-19)-deficient (Mmp19-/-) mice develop an exaggerated bleomycin-induced lung fibrosis, but the mechanisms are unclear. In this study, we explored the effect of MMP-19 deficiency on fibroblast gene expression and cell behavior. Microarray analysis of Mmp19-/- lung fibroblasts revealed the dysregulation of several profibrotic pathways, including ECM formation, migration, proliferation, and autophagy. Functional studies confirmed these findings. Compared with wild-type mice, Mmp19-/- lung fibroblasts showed increased α1 (I) collagen gene and collagen protein production at baseline and after transforming growth factor-ß treatment and increased smooth muscle-α actin expression (P < 0.05). Likewise, Mmp19-deficient lung fibroblasts showed a significant increase in proliferation (P < 0.01) and in transmigration and locomotion over Boyden chambers coated with type I collagen or with Matrigel (P < 0.05). These findings suggest that, in lung fibroblasts, MMP-19 has strong regulatory effects on the synthesis of key ECM components, on fibroblast to myofibroblast differentiation, and in migration and proliferation.


Assuntos
Diferenciação Celular , Movimento Celular , Proliferação de Células , Metaloproteinases da Matriz Secretadas/deficiência , Miofibroblastos/enzimologia , Fibrose Pulmonar/enzimologia , Animais , Autoantígenos/biossíntese , Autoantígenos/genética , Células Cultivadas , Matriz Extracelular/enzimologia , Matriz Extracelular/genética , Matriz Extracelular/patologia , Regulação da Expressão Gênica/genética , Camundongos , Camundongos Knockout , Miofibroblastos/patologia , Colágenos não Fibrilares/biossíntese , Colágenos não Fibrilares/genética , Fibrose Pulmonar/genética , Fibrose Pulmonar/patologia
11.
J Colloid Interface Sci ; 389(1): 42-5, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23062962

RESUMO

Gold nanorods (AuNRs) stabilized by cetyltrimethylammonium bromide (CTAB) were deposited onto crystals of α-cyclodextrin (α-CD) inclusion compounds (ICs) that contained octanethiol (OT) as guest molecules. The nanodecoration was produced specifically at the {001} crystal planes through interaction between the -SH groups of the ICs and the AuNRs.


Assuntos
Ouro/química , Nanotubos/química , alfa-Ciclodextrinas/química , Cetrimônio , Compostos de Cetrimônio/química , Cristalização , Nanotubos/ultraestrutura , Compostos de Sulfidrila/química
12.
Am J Respir Crit Care Med ; 186(8): 752-62, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-22859522

RESUMO

RATIONALE: Idiopathic pulmonary fibrosis (IPF) is a devastating disease characterized by epithelial phenotypic changes and fibroblast activation. Based on the temporal heterogeneity of IPF, we hypothesized that hyperplastic alveolar epithelial cells regulate the fibrotic response. OBJECTIVES: To identify novel mediators of fibrosis comparing the transcriptional signature of hyperplastic epithelial cells and conserved epithelial cells in the same lung. METHODS: Laser capture microscope and microarrays analysis were used to identify differentially expressed genes in IPF lungs. Bleomycin-induced lung fibrosis was evaluated in Mmp19-deficient and wild-type (WT) mice. The role of matrix metalloproteinase (MMP)-19 was additionally studied by transfecting the human MMP19 in alveolar epithelial cells. MEASUREMENTS AND MAIN RESULTS: Laser capture microscope followed by microarray analysis revealed a novel mediator, MMP-19, in hyperplastic epithelial cells adjacent to fibrotic regions. Mmp19(-/-) mice showed a significantly increased lung fibrotic response to bleomycin compared with WT mice. A549 epithelial cells transfected with human MMP19 stimulated wound healing and cell migration, whereas silencing MMP19 had the opposite effect. Gene expression microarray of transfected A549 cells showed that PTGS2 (prostaglandin-endoperoxide synthase 2) was one of the highly induced genes. PTGS2 was overexpressed in IPF lungs and colocalized with MMP-19 in hyperplastic epithelial cells. In WT mice, PTGS2 was significantly increased in bronchoalveolar lavage and lung tissues after bleomycin-induced fibrosis, but not in Mmp19(-/-) mice. Inhibition of Mmp-19 by siRNA resulted in inhibition of Ptgs2 at mRNA and protein levels. CONCLUSIONS: Up-regulation of MMP19 induced by lung injury may play a protective role in the development of fibrosis through the induction of PTGS2.


Assuntos
Ciclo-Oxigenase 2/metabolismo , Fibrose Pulmonar Idiopática/enzimologia , Metaloproteinases da Matriz Secretadas/metabolismo , Animais , Bleomicina , Células Cultivadas , Células Epiteliais/metabolismo , Regulação Enzimológica da Expressão Gênica , Humanos , Fibrose Pulmonar Idiopática/genética , Fibrose Pulmonar Idiopática/patologia , Microdissecção e Captura a Laser , Metaloproteinases da Matriz Secretadas/genética , Camundongos , Camundongos Knockout , Análise de Sequência com Séries de Oligonucleotídeos , Alvéolos Pulmonares/metabolismo , Regulação para Cima
13.
J Nanosci Nanotechnol ; 8(8): 3820-7, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19049136

RESUMO

A new synthesis and stabilization method was developed for paramagnetic nanoparticles composed of nickel and nickel oxides. Nickel/nickel oxides nanoparticles were synthesized by a method based on ligand displacement of bis(1,5-cyclooctadiene)-nickel(0), zerovalent organometallic precursor and simultaneous formation of a thiourea inclusion compound. Nickel/nickel oxides nanoparticles were stabilized with the amphipathic peptide H2N-Cys-Leu-Pro-Phe-Phe-Asp-NH2 having H2N-Leu-Pro-Phe-Phe-Asp-NH2 a peptide with potential properties for Alzheimer's disease therapy. The inclusion compound formed after displacement was characterized by X-ray powder diffraction, and nickel/nickel oxides nanoparticles were characterized using transmission electron microscopy, atomic force microscopy, UV-Visible spectroscopy, X-ray photoelectron spectroscopy, and superconducting quantum interference device magnetometry. In addition, a cell viability assay in primary rat hippocampal neurons was carried out.


Assuntos
Nanopartículas Metálicas/química , Níquel/química , Oligopeptídeos/química , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Estabilidade de Medicamentos , Hipocampo/citologia , Técnicas In Vitro , Neurônios/citologia , Neurônios/efeitos dos fármacos , Oligopeptídeos/farmacologia , Ratos , Ratos Sprague-Dawley
14.
Int J Biochem Cell Biol ; 39(12): 2324-38, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17702637

RESUMO

Pulmonary fibrosis is a common response to a variety of lung injuries, characterized by fibroblast/myofibroblast expansion and abnormal accumulation of extracellular matrix. An increased expression of matrix metalloprotease 9 (MMP9) in human and experimental lung fibrosis has been documented, but its role in the fibrotic response is unclear. We studied the effect of MMP9 overexpression in bleomycin-driven lung fibrosis using transgenic mice expressing human MMP9 in alveolar macrophages (hMMP9-TG). At 8 weeks post-bleomycin, the extent of fibrotic lesions and OH-proline content were significantly decreased in the TG mice compared to the WT mice. The decreased fibrosis in hMMP9-TG mice was preceded by a significant reduction of neutrophils and lymphocytes in bronchoalveolar lavage (BAL) at 1 and 4 weeks post-bleomycin, respectively, as well as by significantly less TIMP-1 than the WT mice. From a variety of cytokines/chemokines investigated, we found that BAL levels of insulin-like growth factor binding protein-3 (IGFBP3) as well as the immunoreactive protein in the lungs were significantly lower in hMMP9-TG mice compared with WT mice despite similar levels of gene expression. Using IGFBP-3 substrate zymography we found that BAL from TG mice at 1 week after bleomycin cleaved IGFBP-3. Further, we demonstrated that MMP9 degraded IGFBP-3 into lower molecular mass fragments. These findings suggest that increased activity of MMP9 secreted by alveolar macrophages in the lung microenvironment may have an antifibrotic effect and provide a potential mechanism involving IGFBP3 degradation.


Assuntos
Bleomicina/toxicidade , Macrófagos Alveolares/enzimologia , Metaloproteinase 9 da Matriz/metabolismo , Fibrose Pulmonar/enzimologia , Animais , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Contagem de Células , Citocinas/análise , Citocinas/metabolismo , Expressão Gênica , Humanos , Hidroxiprolina/metabolismo , Imuno-Histoquímica , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Pulmão/enzimologia , Pulmão/metabolismo , Pulmão/patologia , Linfócitos/citologia , Macrófagos Alveolares/citologia , Macrófagos Alveolares/metabolismo , Metaloproteinase 9 da Matriz/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Camundongos Transgênicos , Neutrófilos/citologia , Peroxidase/análise , Peroxidase/metabolismo , Análise Serial de Proteínas , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo
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