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1.
Int J Nanomedicine ; 16: 4661-4674, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34262274

RESUMO

Purpose: Gold nanoparticles (AuNPs) are widely studied as radiosensitizers, but their radiosensitization in carbon ion radiotherapy is unsatisfactory. There is a lack of in vivo data on the radiosensitization of AuNPs under carbon ion irradiation. This study focused on the radiosensitization effect of AuNPs in the mouse melanoma cell line B16-F10 in vitro and in vivo. Materials and Methods: 11-mercaptoundecanoic acid (11-MUA)-coated gold (Au) nanoparticles (mAuNPs) formulations were prepared and characterized. To verify the radiosensitization effect of mAuNPs, hydroxyl radicals were generated in aqueous solution, and the detection of intracellular reactive oxygen species (ROS) and clone survival were carried out in vitro. The tumor growth rate (TGR) and survival of mice were analyzed to verify the radiosensitization effect of mAuNPs in vivo. The apoptosis of tumor cells was detected, and the expression of key proteins in the apoptosis pathway was verified by immunohistochemistry. Results: The intracellular ROS level in B16-F10 cells was enhanced by mAuNPs under carbon ion irradiation. The sensitization rate of mAuNPs was 1.22 with a 10% cell survival rate. Compared with irradiation alone, the inhibitory effect of mAuNPs combined with carbon ion irradiation on tumor growth was 1.94-fold higher, the survival time of mice was prolonged by 1.75-fold, and the number of apoptotic cells was increased by 1.43-fold. The ratio of key proteins Bax and Bcl2 in the apoptosis pathway was up-regulated, and the expression of caspase-3, a key executor of the apoptosis pathway, was up-regulated. Conclusion: In in vivo and in vitro experiments, mAuNPs showed radiosensitivity to carbon ion irradiation. The sensitization effect of mAuNPs on mice tumor may be achieved by activating the mitochondrial apoptosis pathway and increasing tumor tissue apoptosis. To our best knowledge, the present study is the first in vivo evidence for radiosensitization of mAuNPs in tumor-bearing mice exposed to carbon ion irradiation.


Assuntos
Ácidos Graxos/química , Ouro/química , Radioterapia com Íons Pesados , Nanopartículas Metálicas/química , Compostos de Sulfidrila/química , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células Clonais , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Melanoma Experimental/patologia , Melanoma Experimental/radioterapia , Nanopartículas Metálicas/ultraestrutura , Camundongos Endogâmicos C57BL , Espécies Reativas de Oxigênio/metabolismo , Análise de Sobrevida , Resultado do Tratamento , Carga Tumoral
2.
Int J Mol Sci ; 22(14)2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34299003

RESUMO

Here, we designed paper sheets coated with chitosan, bacterial cellulose (nanofibers), and ZnO with boosted antibacterial and mechanical activity. We investigated the compositions, with ZnO exhibiting two different sizes/shapes: (1) rods and (2) irregular sphere-like particles. The proposed processing of bacterial cellulose resulted in the formation of nanofibers. Antimicrobial behavior was tested using E. coli ATCC® 25922™ following the ASTM E2149-13a standard. The mechanical properties of the paper sheets were measured by comparing tearing resistance, tensile strength, and bursting strength according to the ISO 5270 standard. The results showed an increased antibacterial response (assigned to the combination of chitosan and ZnO, independent of its shape and size) and boosted mechanical properties. Therefore, the proposed composition is an interesting multifunctional mixture for coatings in food packaging applications.


Assuntos
Biopolímeros/química , Biopolímeros/farmacologia , Celulose/química , Quitosana/química , Nanocompostos/química , Embalagem de Produtos/métodos , Óxido de Zinco/química , Anti-Infecciosos , Celulose/ultraestrutura , Escherichia coli , Testes Mecânicos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanocompostos/ultraestrutura , Nanofibras/química , Nanofibras/ultraestrutura , Propriedades de Superfície , Resistência à Tração , Difração de Raios X
3.
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
4.
Theranostics ; 11(14): 6717-6734, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093849

RESUMO

Rationale: Osteoporotic patients suffer symptoms of excessive osteoclastogenesis and impaired osteogenesis, resulting in a great challenge to treat osteoporosis-related bone defects. Based on the positive effect of rare earth elements on bone metabolism and bone regeneration, we try to prove the hypothesis that the La3+ dopants in lanthanum-substituted MgAl layered double hydroxide (La-LDH) nanohybrid scaffolds simultaneously activate osteogenesis and inhibit osteoclastogenesis. Methods: A freeze-drying technology was employed to construct La-LDH nanohybrid scaffolds. The in vitro osteogenic and anti-osteoclastogenic activities of La-LDH nanohybrid scaffolds were evaluated by using ovariectomized rat bone marrow stromal cells (rBMSCs-OVX) and bone marrow-derived macrophages (BMMs) as cell models. The in vivo bone regeneration ability of the scaffolds was investigated by using critical-size calvarial bone defect model of OVX rats. Results: La-LDH nanohybrid scaffolds exhibited three-dimensional macroporous structure, and La-LDH nanoplates arranged perpendicularly on chitosan organic matrix. The La3+ dopants in the scaffolds promote proliferation and osteogenic differentiation of rBMSCs-OVX by activating Wnt/ß-catenin pathway, leading to high expression of ALP, Runx-2, COL-1 and OCN genes. Moreover, La-LDH scaffolds significantly suppressed RANKL-induced osteoclastogenesis by inhibiting NF-κB signaling pathway. As compared with the scaffolds without La3+ dopants, La-LDH scaffolds provided more favourable microenvironment to induce new bone in-growth along macroporous channels. Conclusion: La-LDH nanohybrid scaffolds possessed the bi-directional regulation functions on osteogenesis and osteoclastogenesis for osteoporotic bone regeneration. The modification of La3+ dopants in bone scaffolds provides a novel strategy for osteoporosis-related bone defect healing.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Lantânio/farmacologia , Nanoestruturas/química , Osteogênese/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Tecidos Suporte/química , Animais , Regeneração Óssea/genética , Células Cultivadas , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Dioxigenases/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Lantânio/química , Macrófagos/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Transmissão , NF-kappa B/metabolismo , Nanoestruturas/ultraestrutura , Osteocalcina/metabolismo , Osteogênese/genética , Osteoporose/metabolismo , Ligante RANK/farmacologia , Ratos , Ratos Sprague-Dawley , Tomografia Computadorizada por Raios X , Via de Sinalização Wnt/efeitos dos fármacos , Via de Sinalização Wnt/genética
5.
Molecules ; 26(10)2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-34068079

RESUMO

Noble metals nanoparticles (NPs) and metal oxide NPs are widely used in different fields of application and commercial products, exposing living organisms to their potential adverse effects. Recent evidences suggest their presence in the aquifers water and consequently in drinking water. In this work, we have carefully synthesized four types of NPs, namely, silver and gold NPs (Ag NPs and Au NPs) and silica and titanium dioxide NPs (SiO2 NPs and TiO2 NPs) having a similar size and negatively charged surfaces. The synthesis of Ag NPs and Au NPs was carried out by colloidal route using silver nitrate (AgNO3) and tetrachloroauric (III) acid (HAuCl4) while SiO2 NPs and TiO2 NPs were achieved by ternary microemulsion and sol-gel routes, respectively. Once the characterization of NPs was carried out in order to assess their physico-chemical properties, their impact on living cells was studied. We used the human colorectal adenocarcinoma cells (Caco-2), known as the best representative intestinal epithelial barrier model to understand the effects triggered by NPs through ingestion. Then, we moved to explore how water contamination caused by NPs can be lowered by the ability of three species of aquatic moss, namely, Leptodictyum riparium, Vesicularia ferriei, and Taxiphyllum barbieri, to absorb them. The experiments were conducted using two concentrations of NPs (100 µM and 500 Μm as metal content) and two time points (24 h and 48 h), showing a capture rate dependent on the moss species and NPs type. Then, the selected moss species, able to actively capture NPs, appear as a powerful tool capable to purify water from nanostructured materials, and then, to reduce the toxicity associated to the ingestion of contaminated drinking water.


Assuntos
Absorção Fisico-Química , Organismos Aquáticos/metabolismo , Briófitas/metabolismo , Fenômenos Químicos , Compostos Inorgânicos/química , Mucosa Intestinal/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Modelos Biológicos , Organismos Aquáticos/efeitos dos fármacos , Briófitas/efeitos dos fármacos , Células CACO-2 , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Difusão Dinâmica da Luz , Células Germinativas Vegetais/efeitos dos fármacos , Humanos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Espectrofotometria Ultravioleta , Eletricidade Estática , Titânio/química , Titânio/toxicidade , Difração de Raios X
6.
Theranostics ; 11(14): 6966-6982, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093865

RESUMO

Rationale: Sensitive and accurate imaging of cancer is essential for early diagnosis and appropriate treatment. For generally employed magnetic resonance imaging (MRI) in clinic, comprehending how to enhance the contrast effect of T 1 imaging is crucial for improving the sensitivity of cancer diagnosis. However, there is no study ever to reveal the clear mechanism of how to enhance the effect of T 1 imaging and accurate relationships of influencing factors. Herein, this study aims to figure out key factors that affect the sensitivity of T 1 contrast-enhanced MRI (CE-MRI), thereby to realize sensitive detection of tumors with low dose of CAs. Methods: Manganese oxide (MnO) nanoparticles (NPs) with various sizes and shapes were prepared by thermal decomposition. Factors impacting T 1 CE-MRI were investigated from geometric volume, surface area, crystal face to r 2/r 1 ratio. T 1 CE-MR imaging of liver, hepatic and subcutaneous tumors were conducted with MnO NPs of different shapes. Results: The surface area and occupancy rate of manganese ions have positive impacts on the sensitivity of T 1 CE-MRI, while volume and r 2/r 1 ratio have negative effects. MnO octahedrons have a high r 1 value of 20.07 mM-1s-1 and exhibit an excellent enhanced effect in liver T 1 imaging. ZDS coating facilitates tumor accumulation and cellular uptake, hepatic and subcutaneous tumors could be detected with MnO octahedrons at an ultralow dose of 0.4 mg [Mn]/kg, about 1/10 of clinical dose. Conclusions: This work is the first quantitative study of key factors affecting the sensitivity of T 1 CE-MRI of MnO nanoparticles, which can serve as a guidance for rational design of high-performance positive MRI contrast agents. Moreover, these MnO octahedrons can detect hepatic and subcutaneous tumors with an ultralow dose, hold great potential for sensitive and accurate diagnosis of cancer with lower cost, less dosages and side effects in clinic.


Assuntos
Meios de Contraste/química , Neoplasias Hepáticas/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Compostos de Manganês/química , Nanopartículas Metálicas/química , Óxidos/química , Animais , Linhagem Celular Tumoral , Humanos , Neoplasias Hepáticas/diagnóstico , Masculino , Compostos de Manganês/síntese química , Nanopartículas Metálicas/ultraestrutura , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Transmissão , Óxidos/síntese química , Tamanho da Partícula
7.
Theranostics ; 11(14): 7072-7091, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093872

RESUMO

Simultaneous targeting of both the tumor microenvironment and cancer cells by a single nanomedicine has not been reported to date. Here, we report the dual properties of zero-valent-iron nanoparticle (ZVI-NP) to induce cancer-specific cytotoxicity and anti-cancer immunity. Methods: Cancer-specific cytotoxicity induced by ZVI-NP was determined by MTT assay. Mitochondria functional assay, immunofluorescence staining, Western blot, RT-qPCR, and ChIP-qPCR assays were used to dissect the mechanism underlying ZVI-NP-induced ferroptotic cancer cell death. The therapeutic potential of ZVI-NP was evaluated in immunocompetent mice and humanized mice. Immune cell profiles of allografts and ex vivo cultured immune cells were examined by flow cytometry analysis, RT-qPCR assay, and immunofluorescence. Results: ZVI-NP caused mitochondria dysfunction, intracellular oxidative stress, and lipid peroxidation, leading to ferroptotic death of lung cancer cells. Degradation of NRF2 by GSK3/ß-TrCP through AMPK/mTOR activation was enhanced in such cancer-specific ferroptosis. In addition, ZVI-NP attenuated self-renewal ability of cancer and downregulated angiogenesis-related genes. Importantly, ZVI-NP augmented anti-tumor immunity by shifting pro-tumor M2 macrophages to anti-tumor M1, decreasing the population of regulatory T cells, downregulating PD-1 and CTLA4 in CD8+ T cells to potentiate their cytolytic activity against cancer cells, while attenuating PD-L1 expression in cancer cells in vitro and in tumor-bearing immunocompetent mice. In particular, ZVI-NPs preferentially accumulated in tumor and lung tissues, leading to prominent suppression of tumor growth and metastasis. Conclusions: This dual-functional nanomedicine established an effective strategy to synergistically induce ferroptotic cancer cell death and reprogram the immunosuppressive microenvironment, which highlights the potential of ZVI-NP as an advanced integrated anti-cancer strategy.


Assuntos
Ferroptose/efeitos dos fármacos , Ferro/farmacologia , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/metabolismo , Macrófagos/efeitos dos fármacos , Nanopartículas Metálicas/química , Fator 2 Relacionado a NF-E2/metabolismo , Microambiente Tumoral/efeitos dos fármacos , Aloenxertos , Animais , Antineoplásicos/farmacologia , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/imunologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/imunologia , Imunoprecipitação da Cromatina , Quinase 3 da Glicogênio Sintase/metabolismo , Humanos , Ferro/química , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Macrófagos/metabolismo , Nanopartículas Metálicas/administração & dosagem , Nanopartículas Metálicas/ultraestrutura , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Camundongos SCID , Microscopia Eletrônica de Transmissão , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/patologia , Mitocôndrias/ultraestrutura , Fator 2 Relacionado a NF-E2/genética , Estresse Oxidativo/efeitos dos fármacos , Proteínas Quinases , Serina-Treonina Quinases TOR/metabolismo , Microambiente Tumoral/imunologia
8.
Nat Protoc ; 16(7): 3522-3546, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34089021

RESUMO

Cellular heterogeneity is pervasive and of paramount importance in biology. Single-cell analysis techniques are indispensable for understanding the heterogeneity and functions of cells. Low-copy-number proteins (fewer than 1,000 molecules per cell) perform multiple crucial functions such as gene expression, cellular metabolism and cell signaling. The expression level of low-copy-number proteins of individual cells provides key information for the in-depth understanding of biological processes and diseases. However, the quantitative analysis of low-copy-number proteins in a single cell still remains challenging. To overcome this, we developed an approach called single-cell plasmonic immunosandwich assay (scPISA) for the quantitative measurement of low-copy-number proteins in single living cells. scPISA combines in vivo microextraction for specific enrichment of target proteins from cells and a state-of-the-art technique called plasmon-enhanced Raman scattering for ultrasensitive detection of low-copy-number proteins. Plasmon-enhanced Raman scattering detection relies on the plasmonic coupling effect (hot-spot) between silver-based plasmonic nanotags and a gold-based extraction microprobe, which dramatically enhances the signal intensity of the surface-enhanced Raman scattering of the nanotags and thereby enables sensitivity at the single-molecule level. scPISA is a straightforward and minimally invasive technique, taking only ~6-15 min (from in vivo extraction to Raman spectrum readout). It is generally applicable to all freely floating intracellular proteins provided that appropriate antibodies or alternatives (for example, molecularly imprinted polymers or aptamers) are available. The entire protocol takes ~4-7 d to complete, including material fabrication, single-cell manipulation, protein labeling, signal acquisition and data analysis.


Assuntos
Dosagem de Genes , Imunoensaio/métodos , Proteínas/metabolismo , Análise de Célula Única , Anticorpos/metabolismo , Calibragem , Linhagem Celular Tumoral , Sobrevivência Celular , Análise de Dados , Ouro/química , Humanos , Proteínas Imobilizadas/metabolismo , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Coloração e Rotulagem
9.
Int J Nanomedicine ; 16: 3789-3802, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34103915

RESUMO

Introduction: It has been reported that low-molecular-weight hyaluronic acid (LMWHA) exhibits a potentially beneficial effect on cancer therapy through targeting of CD44 receptors on tumor cell surfaces. However, its applicability towards tumor detection is still unclear. In this regard, LMWHA-conjugated iron (Fe3O4) nanoparticles (LMWHA-IONPs) were prepared in order to evaluate its application for enhancing the T2* weighted MRI imaging sensitivity for tumor detection. Methods: LMWHA and Fe3O4 NPs were produced using γ-ray irradiation and chemical co-precipitation methods, respectively. First, LMWHA-conjugated FITC was prepared to confirm the ability of LMWHA to target U87MG cells using fluorescence microscopy. The hydrodynamic size distribution and dispersion of the IONPs and prepared LMWHA-IONPs were analyzed using dynamic light scattering (DLS). In addition, cell viability assays were performed to examine the biocompatibility of LMWHA and LMWHA-IONPs toward U87MG human glioblastoma and NIH3T3 fibroblast cell lines. The ability of LMWHA-IONPs to target tumor cells was confirmed by detecting iron (Fe) ion content using the thiocyanate method. Finally, time-of-flight secondary ion mass spectrometry (TOF-SIMS) imaging and in vitro magnetic resonance imaging (MRI) were performed to confirm the contrast enhancement effect of LMWHA-IONPs. Results: Florescence analysis results showed that LMWHA-FITC successfully targeted the surfaces of both tested cell types. The ability of LMWHA to target U87MG cells was higher than for NIH3T3 cells. Cell viability experiments showed that the fabricated LMWHA-IONPs possessed good biocompatibility for both cell lines. After co-culturing test cells with the LMWHA-IONPs, detected Fe ion content in the U87MG cells was much higher than that of the NIH3T3 cells in both thiocyanate assays and TOF-SIMs images. Finally, the addition of LMWHA-IONPs to the U87MG cells resulted in an obvious improvement in T2* weighted MR image contrast compared to control NIH3T3 cells. Discussion: Overall, the present results suggest that LMWHA-IONPs fabricated in this study provide an effective MRI contrast agent for improving the diagnosis of early stage glioblastoma in MRI examinations.


Assuntos
Raios gama , Glioblastoma/diagnóstico por imagem , Ácido Hialurônico/química , Ferro/química , Imageamento por Ressonância Magnética , Nanopartículas Metálicas/química , Animais , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular/efeitos dos fármacos , Glioblastoma/patologia , Humanos , Ácido Hialurônico/ultraestrutura , Nanopartículas Metálicas/ultraestrutura , Camundongos , Peso Molecular , Células NIH 3T3 , Ácido Oleico/química , Tamanho da Partícula
10.
Int J Mol Sci ; 22(10)2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-34065835

RESUMO

The discovery of eco-friendly, rapid, and cost-effective compounds to control diseases caused by microbes and insects are the main challenges. Herein, the magnesium oxide nanoparticles (MgO-NPs) are successfully fabricated by harnessing the metabolites secreted by Penicillium chrysogenum. The fabricated MgO-NPs were characterized using UV-Vis, XRD, TEM, DLS, EDX, FT-IR, and XPS analyses. Data showed the successful formation of crystallographic, spherical, well-dispersed MgO-NPs with sizes of 7-40 nm at a maximum wavelength of 250 nm. The EDX analysis confirms the presence of Mg and O ions as the main components with weight percentages of 13.62% and 7.76%, respectively. The activity of MgO-NPs as an antimicrobial agent was investigated against pathogens Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans, and exhibited zone of inhibitions of 12.0 ± 0.0, 12.7 ± 0.9, 23.3 ± 0.8, 17.7 ± 1.6, and 14.7 ± 0.6 mm respectively, at 200 µg mL-1. The activity is decreased by decreasing the MgO-NPs concentration. The biogenic MgO-NPs exhibit high efficacy against different larvae instar and pupa of Anopheles stephensi, with LC50 values of 12.5-15.5 ppm for I-IV larvae instar and 16.5 ppm for the pupa. Additionally, 5 mg/cm2 of MgO-NPs showed the highest protection percentages against adults of Anopheles stephensi, with values of 100% for 150 min and 67.6% ± 1.4% for 210 min.


Assuntos
Anopheles/efeitos dos fármacos , Anti-Infecciosos/farmacologia , Inseticidas/farmacologia , Óxido de Magnésio/farmacologia , Penicillium chrysogenum/crescimento & desenvolvimento , Animais , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Bacillus subtilis/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Cristalografia por Raios X , Escherichia coli/efeitos dos fármacos , Química Verde , Inseticidas/química , Inseticidas/isolamento & purificação , Larva/efeitos dos fármacos , Óxido de Magnésio/química , Óxido de Magnésio/isolamento & purificação , Metabolômica , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Penicillium chrysogenum/química , Pseudomonas aeruginosa/efeitos dos fármacos , Pupa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
11.
Molecules ; 26(10)2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-34064907

RESUMO

The constant increase of antibiotic-resistant bacteria demands the design of novel antibiotic-free materials. The combination of antibacterials in a biocompatible biomaterial is a very promising strategy to treat infections caused by a broader spectrum of resistant pathogens. Here, we combined two antibacterials, silver nanoparticles (AgNPs) and living probiotics (Lactobacillus fermentum, Lf), using bacterial cellulose (BC) as scaffold. By controlling the loading of each antibacterial at opposite BC sides, we obtained a two-sided biomaterial (AgNP-BC-Lf) with a high density of alive and metabolically active probiotics on one surface and AgNPs on the opposite one, being probiotics well preserved from the killer effect of AgNPs. The resulting two-sided biomaterial was characterized by Field-Emission Scanning Electron Microscopy (FESEM) and Confocal Laser Scanning Microscopy (CLSM). The antibacterial capacity against Pseudomonas aeruginosa (PA), an opportunistic pathogen responsible for a broad range of skin infections, was also assessed by agar diffusion tests in pathogen-favorable media. Results showed an enhanced activity against PA when both antibacterials were combined into BC (AgNP-BC-Lf) with respect to BC containing only one of the antibacterials, BC-Lf or AgNP-BC. Therefore, AgNP-BC-Lf is an antibiotic-free biomaterial that can be useful for the therapy of topical bacterial infections.


Assuntos
Antibacterianos/farmacologia , Celulose/farmacologia , Nanopartículas Metálicas/química , Probióticos/farmacologia , Prata/farmacologia , Materiais Biocompatíveis , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/efeitos dos fármacos
12.
Int J Biol Macromol ; 182: 1409-1418, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33965484

RESUMO

The present work reported synthesis, characterization, and biocompatibility of starch encapsulated silver nanoparticles (St-PF-AgNPs) and their antibacterial activity. The synthesis of St-PF-AgNPs involved in two steps: (i) synthesis of the biogenic silver nanoparticles using the fungal extracts (PF-AgNPs); and, (ii) encapsulation of starch in PF-AgNPs (St-PF-AgNPs). The surface plasmon resonance was found at 420 nm for the PF-AgNPs while it was at 260 and 420 nm for the St-PF-AgNPs. FTIR spectrum demonstrated the capping and encapsulation of the fungal extracts and starch in PF-AgNPs and St-PF-AgNPs. The XRD and TEM-EDS confirmed the crystalline nature, spherical-shaped , and polydispersed- PF-AgNPs and St-PF-AgNPs with strong signals of Ag. The St-PF-AgNPs showed a Z-average size of 115.2 d.nm and zeta potential of -17.8 (mV) as indicated by DLS and zeta potentials. The cytotoxicity results demonstrated higher toxicity of PF-AgNPs than St-PF-AgNPs in HEK293 cells. The antibacterial activity of St-PF-AgNPs were higher than PF-AgNPs in S. aureus. Overall, this work concluded that the starch encapsulation significantly increased the antibacterial activity of PF-AgNPs and this opens a new avenue for the treatment of bacterial infections through the sustained release of PF-AgNPs to target pathogenic bacterial cells.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Nanopartículas Metálicas/química , Prata/química , Amido/química , Bactérias/efeitos dos fármacos , Bactérias/ultraestrutura , Morte Celular/efeitos dos fármacos , Difusão Dinâmica da Luz , Fungos/química , Células HEK293 , Humanos , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Difração de Raios X
13.
Int J Biol Macromol ; 182: 2003-2018, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34029584

RESUMO

The presence of saccharin (SH) could be efficiently sensed (in the concentration range of 5 × 10-5 M to 5 × 10-1 M) through the interference synthesis of gum ghatti (GG) capped silver nanoparticles (GGAgNps). The synthesis used sodium borohydride and gum ghatti (GG) as the reducing and capping agents respectively. The strong hydrogen-bonding recognition between GG and SH was responsible for the interference. The intensity of the SPR peak of GGAgNps was found linearly dependent on [SH]. The SH detection was further enhanced when combo capping comprising of GG and chitosan (Ch) (in 1:1 weight ratio) was used while the use of gum acacia (GA) in place of Ch (in combo) decreased the detection sensitivity. The combo polysaccharide solutions had non-Newtonian behaviour and shear thinning property like GG. The method was also applied for the successful detection of SH in commercially available real juice samples.


Assuntos
Nanopartículas Metálicas/química , Gomas Vegetais/química , Sacarina/análise , Prata/química , Boroidretos/química , Concentração de Íons de Hidrogênio , Nanopartículas Metálicas/ultraestrutura , Tamanho da Partícula , Polissacarídeos/química , Nitrato de Prata/química , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Edulcorantes/análise , Fatores de Tempo , Viscosidade
14.
Chem Asian J ; 16(13): 1807-1819, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34009749

RESUMO

A new route has been developed to design plasmonic pollen grain-like nanostructures (PGNSs) as surface-enhanced Raman scattering (SERS)-active substrate. The nanostructures consisting of silver (Ag) and gold (Au) nanoparticles along with zinc oxide (ZnO) nanoclusters as spacers were found highly SERS-active. The morphology of PGNSs and those obtained in the intermediate stage along with each elemental evolution has been investigated by a high-resolution field emission scanning electron microscopy. The optical band gaps and crystal structure have been identified by UV-vis absorption and X-ray powder diffraction (XRD) measurements, respectively. For PGNSs specimen, three distinct absorption bands related to constituent elements Ag, Au, and ZnO were observed, whereas XRD peaks confirmed the existence of Ag, Au, and ZnO within the composition of PGNSs. SERS-activity of PGNSs was confirmed using Rhodamine 6G (R6G) as Raman-active dyes. Air-cooled solid-state laser kits of 532 nm were used as excitation sources in SERS measurements. SERS enhancement factor was estimated for PGNSs specimen and was found as high as 3.5×106 . Finite difference time domain analysis was carried out to correlate the electromagnetic (EM) near-field distributions with the experiment results achieved under this investigation. EM near-field distributions at different planes were extracted for s-, p- and 45° of incident polarizations. EM near-field distributions for such nanostructures as well as current density distributions under different circumstances were demonstrated and plausible scenarios were elucidated given SERS enhancements. Such generic fabrication route as well as correlated investigation is not only indispensable to realize the potential of SERS applications but also unveil the underneath plasmonic characteristics of complex SERS-active nanostructures.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Pólen , Prata/química , Análise Espectral Raman , Animais , Nanopartículas Metálicas/ultraestrutura , Camundongos , Propriedades de Superfície , Óxido de Zinco/química
15.
Anal Bioanal Chem ; 413(16): 4207-4215, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33987702

RESUMO

Accurate and rapid quantitative detection of pesticide and pollutant levels in the actual sample can aid in protecting food security, environmental security, and human health. A high Raman enhancement factor and good repeatability of the surface-enhanced Raman spectroscopy (SERS) substrates are favorable to quantitative analysis. Herein, a quantitative SERS sensor based on constructed self-assembled plasmonic Au@Ag heterogeneous nanocuboids (Au@Ag NCs) monolayer was developed. The sensor was used to quantitatively detect the trace pesticides extracted from pear surfaces and pollutants in fishpond water. Densely packed Au@Ag NCs fabricated into large-scale monolayer films were chemically functionalized using 4-methyl-thiobenzoic acid (4-MBA) at the organic/aqueous interface, in which plentiful nanogaps contribute to increase hotspots. Their sharp corners and edges make the sensor have high SERS performance through providing abundant "hot spots." The obtained optically SERS-based sensor with uniform liquid-state interfacial nanoparticle arrays appeared to have nice SERS performance and uniformity using crystal violet (CV) as a probe molecule. In particular, the proposed SERS sensor was applied for quantitative detection of thiabendazole (TBZ) extracted from pear surfaces and malachite green (MG) in fishpond water down to levels of 0.0105 nM and 0.87 nM for SERS assay respectively. As a result, our proposed SERS quantitative detection strategy is quite preferred to on-site analysis and supervision of contaminant in food samples.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Praguicidas/análise , Prata/química , Análise Espectral Raman/métodos , Poluentes Químicos da Água/análise , Água Doce/análise , Frutas/química , Nanopartículas Metálicas/ultraestrutura , Pyrus/química , Corantes de Rosanilina/análise , Tiabendazol/análise
16.
Nat Commun ; 12(1): 2921, 2021 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-34012021

RESUMO

Spatial light modulators have become an essential tool for advanced microscopy, enabling breakthroughs in 3D, phase, and super-resolution imaging. However, continuous spatial-light modulation that is capable of capturing sub-millisecond microscopic motion without diffraction artifacts and polarization dependence is challenging. Here we present a photothermal spatial light modulator (PT-SLM) enabling fast phase imaging for nanoscopic 3D reconstruction. The PT-SLM can generate a step-like wavefront change, free of diffraction artifacts, with a high transmittance and a modulation efficiency independent of light polarization. We achieve a phase-shift > π and a response time as short as 70 µs with a theoretical limit in the sub microsecond range. We used the PT-SLM to perform quantitative phase imaging of sub-diffractional species to decipher the 3D nanoscopic displacement of microtubules and study the trajectory of a diffusive microtubule-associated protein, providing insights into the mechanism of protein navigation through a complex microtubule network.


Assuntos
Microscopia de Contraste de Fase/métodos , Proteínas de Ciclo Celular/metabolismo , Simulação por Computador , Ouro , Humanos , Imageamento Tridimensional/métodos , Imageamento Tridimensional/estatística & dados numéricos , Luz , Nanopartículas Metálicas/ultraestrutura , Microscopia de Força Atômica , Microscopia de Interferência/métodos , Microscopia de Interferência/estatística & dados numéricos , Microscopia de Contraste de Fase/estatística & dados numéricos , Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/metabolismo , Microtúbulos/ultraestrutura , Nanotecnologia , Nanotubos/ultraestrutura , Fenômenos Ópticos , Proteínas de Schizosaccharomyces pombe/metabolismo , Fatores de Tempo , Tubulina (Proteína)/metabolismo
17.
Biomed Res Int ; 2021: 5572252, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33997013

RESUMO

Objective: Vaccinium genus plants have medicinal value, of which Vaccinium arctostaphylos (Caucasian whortleberry or Qare-Qat in the local language) is the only available species in Iran. Public tendency to use herbal remedies and natural products such as synthesized nanoparticles is increasing due to the proof of the destructive side effects of chemical drugs. Nanosilver products have been effective against more than 650 microbe types. This study was aimed at assessing the possibility of green synthesis of silver nanoparticles using Vaccinium arctostaphylos aqueous extract and at evaluating its antibacterial properties, as well. Materials and Methods: In order to synthesize silver nanoparticles, different volumes of Vaccinium arctostaphylos aqueous extract (3, 5, 10, 15, and 30 ml) were assessed with different silver nitrate solution concentrations (0.5, 1, 3, 5, and 10 mM) and different reaction time durations (1, 3, 5, 10, and 20 minutes) at room temperature using a rotary shaker with a speed of 150 rpm. Ultraviolet-visible (UV-Vis) spectroscopy, X-ray diffraction analysis (XRD), Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM) were carried out. The antibacterial activity of the aqueous extract and the synthesized nanoparticles was evaluated, as well. Results: Silver nanoparticle formation process was confirmed with XRD analysis, transmission electron microscopy (TEM), and FTIR spectroscopy. The UV-Vis spectroscopy of silver colloidal nanoparticles showed a surface plasmon resonance peak at 443 nm under optimal conditions (3 ml aqueous extract volume, 1 mM silver nitrate solution concentration, and 3 min reaction time under sunlight exposure). The reduction of silver ions to silver nanoparticles in solution was confirmed, as well. Based on X-ray diffraction analysis, the size of silver nanoparticles was in the range of 7-16 nm. TEM images showed an even distribution of silver nanoparticles, with a spherical shape. FTIR spectroscopy demonstrated the presence of different functional groups of oxygenated compounds such as carboxyl, hydroxyl, and nitrogenous groups. The antibacterial properties of the synthesized nanoparticles were confirmed. Conclusion: The synthesized nanoparticles showed more antibacterial properties against gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus) than gram-negative ones (Escherichia coli and Salmonella enteritidis).


Assuntos
Antibacterianos/farmacologia , Química Verde , Nanopartículas Metálicas/química , Extratos Vegetais/química , Prata/farmacologia , Vaccinium/química , Bactérias/efeitos dos fármacos , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Luz Solar , Fatores de Tempo , Vaccinium/anatomia & histologia , Difração de Raios X
18.
Int J Nanomedicine ; 16: 3021-3040, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33935497

RESUMO

Purpose: Silver nanoparticles (AgNPs) are one of the most commonly investigated nanomaterials, especially due to their biomedical applications. However, their excellent cytotoxic and antimicrobial activity is often compromised in biological media due to nanoparticle aggregation. In this work, the aggregation behavior and the related biological activity of three different samples of citrate capped silver nanoparticles, with mean diameters of 10, 20, and 50 nm, respectively, were examined. Methods: Following nanoparticle synthesis and characterization with transmission electron microscopy, their aggregation behavior under various pH values, NaCl, glucose, and glutamine concentrations, furthermore in cell culture medium components such as Dulbecco's Modified Eagle's Medium and fetal bovine serum, was assessed through dynamic light scattering and ultraviolet-visible spectroscopy. Results: The results indicated that acidic pH and physiological electrolyte content universally induce micron-scale aggregation, which can be mediated by biomolecular corona formation. Remarkably, larger particles demonstrated higher resistance against external influences than smaller counterparts. In vitro cytotoxicity and antimicrobial assays were performed by treating cells with nanoparticulate aggregates in differing stages of aggregation. Conclusion: Our results revealed a profound association between colloidal stability and toxicity of AgNPs, as extreme aggregation led to the complete loss of biological activity. The higher degree of aggregation resistance observed for larger particles had a significant impact on the in vitro toxicity, since such samples retained more of their activity against microbes and mammalian cells. These findings lead to the conclusion that aiming for the smallest possible nanoparticles might not be the best course of action, despite the general standpoint of the relevant literature.


Assuntos
Nanopartículas Metálicas/química , Tamanho da Partícula , Prata/química , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Ácido Cítrico/química , Meios de Cultura/química , Difusão Dinâmica da Luz , Fungos/efeitos dos fármacos , Glucose/farmacologia , Glutamina/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana , Cloreto de Sódio/química
19.
Biochem Biophys Res Commun ; 557: 240-246, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-33894409

RESUMO

Platinum-based concurrent chemo-radiotherapy is the most common strategy for the treatment of Nasopharyngeal carcinoma. However, low efficacy and side effects are the two major problems associated with this approach. Therefore, it is urgent need to explore novel therapeutic modalities to meet clinically standards. Photothermal therapy (PTT) and photodynamic therapy (PDT) are non-invasive and light trigger modalities received great attention to overcome the limitations and significantly improved cancer therapy. Here, we developed acidity surface charge transformable nanocluster (NCs) composed of Indocyanine green (ICG), Fe3O4, and Palmitoyl ascorbic acid (PA) with pH-responsive PEG-b-PAEMA-PDMA for enhanced synergistic PDT/PTT. NCs has the neutral hydrophilic surface helps to prolong blood circulation and instantly transformed to positively charged surface at tumoral acidic pH (6.5), which promoted the cellular uptake. Under laser irradiation (808 nm, 1 W/cm2), NCs produced PTT effect, concurrently it converts singlet oxygen (1O2) into H2O2, which can be further involved in Fenton reaction and produce toxic hydroxyl radical (•OH) enhances therapy efficacy. In vitro experiments on HNE-1 cancer cells showed improved intracellular uptake of NCs at low pH and simultaneously induced higher cytotoxicity medicated by synergetic PDT/PTT effect. In vivo therapeutic study revealed that NCs treatment under laser irradiation showed superior inhibition of tumor growth in HNE-1 tumor bearing mice model. Taken together, the present findings suggest that NCs could be used as "all in one" nano theranostic agent for enhanced PDT/PTT of cancer therapy.


Assuntos
Compostos Férricos/química , Peróxido de Hidrogênio/química , Nanopartículas Metálicas/química , Nanopartículas Metálicas/efeitos da radiação , Carcinoma Nasofaríngeo/tratamento farmacológico , Neoplasias Nasofaríngeas/tratamento farmacológico , Fotoquimioterapia/métodos , Terapia Fototérmica/métodos , Animais , Ácido Ascórbico/análogos & derivados , Ácido Ascórbico/química , Disponibilidade Biológica , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Feminino , Humanos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Verde de Indocianina/química , Lasers , Nanopartículas Metálicas/ultraestrutura , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Polímeros/química , Medicina de Precisão , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Int J Nanomedicine ; 16: 2849-2877, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33883895

RESUMO

Background: Exosomes are endosome-derived nano-sized vesicles that have emerged as important mediators of intercellular communication and play significant roles in various diseases. However, their applications are rigorously restricted by the limited secretion competence of cells. Therefore, strategies to enhance the production and functions of exosomes are warranted. Studies have shown that nanomaterials can significantly enhance the effects of cells and exosomes in intercellular communication; however, how palladium nanoparticles (PdNPs) enhance exosome release in human leukemia monocytic cells (THP-1) remains unclear. Therefore, this study aimed to address the effect of PdNPs on exosome biogenesis and release in THP-1 cells. Methods: Exosomes were isolated by ultracentrifugation and ExoQuickTM and characterized by dynamic light scattering, nanoparticle tracking analysis system, scanning electron microscopy, transmission electron microscopy, EXOCETTM assay, and fluorescence polarization. The expression levels of exosome markers were analyzed via quantitative reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay. Results: PdNP treatment enhanced the biogenesis and release of exosomes by inducing oxidative stress, endoplasmic reticulum stress, apoptosis, and immunomodulation. The exosomes were spherical in shape and had an average diameter of 50-80 nm. Exosome production was confirmed via total protein concentration, exosome counts, acetylcholinesterase activity, and neutral sphingomyelinase activity. The expression levels of TSG101, CD9, CD63, and CD81 were significantly higher in PdNP-treated cells than in control cells. Further, cytokine and chemokine levels were significantly higher in exosomes isolated from PdNP-treated THP-1 cells than in those isolated from control cells. THP-1 cells pre-treated with N-acetylcysteine or GW4869 showed significant decreases in PdNP-induced exosome biogenesis and release. Conclusion: To our knowledge, this is the first study showing that PdNPs stimulate exosome biogenesis and release and simultaneously increase the levels of cytokines and chemokines by modulating various physiological processes. Our findings suggest a reasonable approach to improve the production of exosomes for various therapeutic applications.


Assuntos
Apoptose/efeitos dos fármacos , Estresse do Retículo Endoplasmático , Exossomos/metabolismo , Imunomodulação/efeitos dos fármacos , Leucemia/patologia , Nanopartículas Metálicas/toxicidade , Estresse Oxidativo , Paládio/toxicidade , Acetilcolinesterase/metabolismo , Acetilcisteína/farmacologia , Compostos de Anilina/farmacologia , Antioxidantes/metabolismo , Compostos de Benzilideno/farmacologia , Biomarcadores Tumorais/metabolismo , Caspases/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Dano ao DNA , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Humanos , Leucemia/sangue , Nanopartículas Metálicas/ultraestrutura , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/patologia , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Tamanho da Partícula , Esfingomielina Fosfodiesterase/metabolismo , Células THP-1
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