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1.
Int J Nanomedicine ; 16: 2123-2136, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33731994

RESUMO

Purpose: Nanomaterial-based drug-delivery systems allowing for effective targeted delivery of smallmolecule chemodrugs to tumors have revolutionized cancer therapy. Recently, as novel nanomaterials with outstanding physicochemical properties, boron nitride nanospheres (BNs) have emerged as a promising candidate for drug delivery. However, poor dispersity and lack of tumor targeting severely limit further applications. In this study, cancer cell-membrane biomimetic BNs were designed for targeted anticancer drug delivery. Methods: Cell membrane extracted from HeLa cells (HM) was used to encapsulate BNs by physical extrusion. Doxorubicin (Dox) was loaded onto HM-BNs as a model drug. Results: The cell-membrane coating endowed the BNs with excellent dispersibility and cytocompatibility. The drug-release profile showed that the Dox@HM-BNs responded to acid pH, resulting in rapid Dox release. Enhanced cellular uptake of Dox@HM-BNs by HeLa cells was revealed because of the homologous targeting of cancer-cell membranes. CCK8 and live/dead assays showed that Dox@HM-BNs had stronger cytotoxicity against HeLa cells, due to self-selective cellular uptake. Finally, antitumor investigation using the HeLa tumor model demonstrated that Dox@HM-BNs possessed much more efficient tumor inhibition than free Dox or Dox@BNs. Conclusion: These findings indicate that the newly developed HM-BNs are promising as an efficient tumor-selective drug-delivery vehicle for tumor therapy.


Assuntos
Materiais Biomiméticos/química , Compostos de Boro/química , Membrana Celular/patologia , Terapia de Alvo Molecular , Nanosferas/química , Neoplasias/patologia , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Peso Corporal/efeitos dos fármacos , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Endocitose/efeitos dos fármacos , Feminino , Células HEK293 , Humanos , Camundongos Endogâmicos BALB C , Nanosferas/ultraestrutura , Neoplasias/tratamento farmacológico , Espectrometria por Raios X , Distribuição Tecidual/efeitos dos fármacos
2.
Int J Nanomedicine ; 16: 895-904, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33603358

RESUMO

Purpose: Worldwide water contamination treatment and water security are essential for all living organisms. Among various water contaminants, dye, and bacteria pollution needs to be solved urgently. Methods and Results: In this work, a ceramic sheet from monodisperse, porous silica nanospheres (SiO2 NSs) with an average diameter of 220 was prepared. The prepared SiO2 ceramic sheets were investigated as a "filtration" material in removing dyes (alcian blue, AB; and methylene blue, MB) and bacteria (E. coli and S. aureus). The obtained sheets had efficient adsorption efficiency of 98.72% (for AB) and 97.35% (for MB), and a high adsorption capacity for AB is 220 (mg/g), for MB is 176 (mg/g). Furthermore, these SiO2 ceramic sheets had a high recycling capability for removing dyes by calcination. Being modified by Ag nanoclusters, the ceramic sheets present a strong bactericidal function. Conclusion: Our results demonstrated that the obtained SiO2 non-sintered ceramic sheets is rapid and efficient in the filtration of dyes and bacteria from polluted water.


Assuntos
Bactérias/isolamento & purificação , Cerâmica/química , Corantes/isolamento & purificação , Nanosferas/química , Dióxido de Silício/química , Prata/química , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Azul Alciano/química , Antibacterianos/farmacologia , Corantes/química , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Azul de Metileno/química , Testes de Sensibilidade Microbiana , Nanosferas/ultraestrutura , Porosidade , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação , Água
3.
Int J Nanomedicine ; 16: 579-589, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33531802

RESUMO

Purpose: Breast cancer is one of the most lethal types of cancer in women. Curcumin showed therapeutic potential against breast cancer, but applying that by itself does not lead to the associated health benefits due to its poor bioavailability, which appears to be primarily due to poor absorption, rapid metabolism, and rapid elimination. Moreover, poor water solubility of curcumin causes accumulation of a high concentration of curcumin and so decrease its permeability to the cell. Many strategies are employed to reduce curcumin metabolism such as adjuvants and designing novel delivery systems. Therefore, in this study sodium alginate and chitosan were used to synthesize the hydrogels that are known as biocompatible, hydrophilic and low toxic drug delivery systems. Also, folic acid was used to link to chitosan in order to actively targetfolate receptors on the cells. Methods: Chitosan-ß-cyclodextrin-TPP-Folic acid/alginate nanoparticles were synthesized and then curcumin was loaded on them. Interaction between the constituents of the particles was characterized by FTIR spectroscopy. Morphological structures of samples were studied by FE-SEM. Release profile of curcumin was determined by dialysis membrane. The cytotoxic test was done on the Kerman male breast cancer (KMBC-10) cell line by using MTT assay. The viability of cells was detected by fluorescent staining. Gene expression was investigated by real-time PCR. Results: The encapsulation of curcumin into nano-particles showed an almost spherical shape and an average particle size of 155 nm. In vitro cytotoxicity investigation was indicated as dose-respond reaction against cancer breast cells after 24 h incubation. On the other hand, in vitro cell uptake study revealed active targeting of CUR-NPs into spheroids. Besides, CXCR 4 expression was detected about 30-fold less than curcumin alone. The CUR-NPs inhibited proliferation and increased apoptosis in spheroid human breast cancer cells. Conclusion: Our results showed the potential of NPs as an effective candidate for curcumin delivery to the target tumor spheroids that confirmed the creatable role of folate receptors.


Assuntos
Alginatos/química , Quitosana/química , Curcumina/farmacologia , Nanosferas/química , Esferoides Celulares/patologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Fluorescência , Ácido Fólico/uso terapêutico , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Masculino , Nanosferas/ultraestrutura , Tamanho da Partícula , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Esferoides Celulares/efeitos dos fármacos
4.
ACS Appl Mater Interfaces ; 13(2): 2179-2188, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33405501

RESUMO

The need to increase agricultural yield has led to an extensive use of antibiotics against plant pathogens, which has resulted in the emergence of resistant strains. Therefore, there is an increasing demand for new methods, preferably with lower chances of developing resistant strains and a lower risk to the environment or public health. Many Gram-negative bacterial pathogens use quorum sensing, a population-density-dependent regulatory mechanism, to monitor the secretion of N-acyl-homoserine lactones (AHLs) and pathogenicity. Therefore, quorum sensing represents an attractive antivirulence target. AHL lactonases hydrolyze AHLs and have potential antibacterial properties; however, their use is limited by thermal instability and durability, or low activity. Here, we demonstrate that an AHL lactonase from the phosphotriesterase-like lactonase family exhibits high activity with the AHL secreted from the plant pathogen Erwinia amylovora and attenuates infection in planta. Using directed enzyme evolution, we were able to increase the enzyme's temperature resistance (T50, the temperature at which 50% of the activity is retained) by 8 °C. Then, by performing enzyme encapsulation in nanospherical capsules composed of tertbutoxycarbonyl-Phe-Phe-OH peptide, the shelf life was extended for more than 5 weeks. Furthermore, the encapsulated and free mutant were able to significantly inhibit up to 70% blossom's infection in the field, achieving the same efficacy as seen with antibiotics commonly used today to treat the plant pathogen. We conclude that specific AHL lactonase can inhibit E. amylovora infection in the field, as it degrades the AHL secreted by this plant pathogen. The combination of directed enzyme evolution and peptide nanostructure encapsulation significantly improved the thermal resistance and shelf life of the enzyme, respectively, increasing its potential in future development as antibacterial treatment.


Assuntos
Hidrolases de Éster Carboxílico/farmacologia , Erwinia amylovora/efeitos dos fármacos , Mycobacterium tuberculosis/enzimologia , Nanosferas/química , Doenças das Plantas/prevenção & controle , Percepção de Quorum/efeitos dos fármacos , Acil-Butirolactonas/metabolismo , Hidrolases de Éster Carboxílico/administração & dosagem , Hidrolases de Éster Carboxílico/genética , Evolução Molecular Direcionada/métodos , Enzimas Imobilizadas/administração & dosagem , Enzimas Imobilizadas/genética , Enzimas Imobilizadas/farmacologia , Erwinia amylovora/fisiologia , Modelos Moleculares , Peptídeos/química , Doenças das Plantas/microbiologia , Pyrus/microbiologia
5.
Carbohydr Polym ; 252: 117135, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33183594

RESUMO

Cyclodextrin-calixarene giant amphiphiles that can self-assemble into nanospheres or nanovesicles have the ability to encapsulate the anticancer hydrophobic drugs docetaxel, temozolomide and combretastatin A-4 with encapsulation efficiencies >80% and deliver them to tumoral cells, enhancing their therapeutic efficacy by 1-3 orders of magnitude. These amphiphiles were modified by inserting a disulfide bridge confering them redox responsiveness. Disassembly of the resulting nanocompounds and cargo release was favored by high glutathione levels mimicking those present in the tumor microenvironment. Anticancer drug-loaded nanoformulations inhibited prostate, breast, glioblastoma, colon or cervix cancer cell lines proliferation with IC50 values markedly below those observed for the free drugs. Cell-cycle analysis indicated a similar mechanism of action for drug-loaded nanocompounds and free drugs. The results strongly suggest that the cyclodextrin-calixarene heterodimer prototype is an excellent scaffold for nanoformulations aimed to deliver anticancer drugs with limited bioavailability due to low solubility to tumoral cells, markedly increasing their effectivity.


Assuntos
Antineoplásicos , Calixarenos/química , Proliferação de Células/efeitos dos fármacos , Ciclodextrinas/química , Portadores de Fármacos , Nanosferas/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Disponibilidade Biológica , Linhagem Celular Tumoral , Portadores de Fármacos/síntese química , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Humanos , Interações Hidrofóbicas e Hidrofílicas
6.
Food Chem ; 335: 127610, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32738532

RESUMO

Although collagen peptides have been proved to possess wide applications in functional foods, cosmetics, medical materials and pharmaceuticals, the production of collagen peptides are deeply affected by proteases and substrate. In this study, the scalable-synthesis sulfonated polystyrene (SPS) nanospheres were utilized as accessible supports for efficient subtilisin immobilization. Detailed characterizations through SEM-EDS, TEM, TGA and FT-IR confirmed the undamaged formation of the SPS-subtilisin. Owing to the moderate hydrophobic effect and electrostatic interaction, the SPS-subtilisin could achieve 397.15 mg/g enzyme loading and 77.3% activity recovery. The tilapia skin collagen, as a resource-rich raw material, was hydrolyzed by the prepared immobilized subtilisin. The antioxidant activity of the attained peptides was verified. With the mass spectrometry and molecular docking analysis of product peptides sequences, representative peptides were synthesized and their anti-oxidation capacity and mechanism were affirmed, which further verified the undiminished catalytic ability of immobilized subtilisin.


Assuntos
Colágeno/química , Nanosferas/química , Peptídeo Hidrolases/química , Peptídeos/química , Poliestirenos/química , Catálise , Endopeptidases/química , Enzimas Imobilizadas/química , Interações Hidrofóbicas e Hidrofílicas , Simulação de Acoplamento Molecular , Espectroscopia de Infravermelho com Transformada de Fourier
7.
Methods Mol Biol ; 2207: 151-161, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33113134

RESUMO

Common chemotherapeutic drugs exhibit no specificity for cancer cells and destroy simultaneously healthy cells exhibiting high toxicity and reduced efficacy. The use of nanotechnology, especially of drug delivery systems to the size of the nanoscale, provides rational drug design solutions. Such nanomaterials may have a range of desired characteristics (lack of toxicity, response to certain characteristics of the cancer cells, antimicrobial properties, specific activity, etc.) in order to achieve targeted cancer therapy. In this chapter, polymeric systems with core-shell structure are synthesized, characterized, and studied as potent drug delivery devices for targeted cancer therapy. These polymeric systems are based on natural polysaccharides like cellulose, chitosan, and their derivatives, in combination with synthetic polymer. Polymethylmethacrylate (PMMA) nanospheres are used as a core in order to coat the surface with multiple layers of polysaccharides via layer-by-layer deposition. This design is advantageous due to the use of water as the appropriate solvent. Fabricated polymeric carriers are characterized structurally by AT-IR spectroscopy and morphologically by transmission (TEM) and scanning electron microscopy (SEM). Finally, daunorubicin, an anticancer agent, was encapsulated as a drug model into the carriers.


Assuntos
Antineoplásicos , Celulose/química , Quitosana/química , Portadores de Fármacos , Nanosferas , Neoplasias/tratamento farmacológico , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Portadores de Fármacos/síntese química , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/farmacologia , Humanos , Nanosferas/química , Nanosferas/uso terapêutico , Neoplasias/metabolismo , Neoplasias/patologia , Polimetil Metacrilato/química
8.
Int J Nanomedicine ; 15: 5165-5177, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764943

RESUMO

Background: The integration of NIR photothermal therapy and chemotherapy is considered as a promising technique for future cancer therapy. Hollow Prussian nanospheres have attracted much attention due to excellent near-infrared photothermal conversion effect and drug-loading capability within an empty cavity. However, to date, the hollow Prussian nanospheres have been prepared by a complex procedure or in organic media, and their shell thickness and size cannot be controlled. Thus, a simple and controllable route is highly desirable to synthesize hollow Prussian nanospheres with controllable parameters. Materials and Methods: Here, in our designed synthesis route, the traditional FeCl3 precursor was replaced with Fe2O3 nanospheres, and then the Prussian blue (PB) nanoparticles were engineered into hollow-structured PB (HPB) nanospheres through an interface reaction, where the Fe2O3 colloidal template provides Fe3+ ions. The reaction mechanism and control factors of HPB nanospheres were systematically investigated. Both in vitro and in vivo biological effects of the as-synthesized HPB nanospheres were evaluated in detail. Results: Through systematical experiments, a solvent-mediated interface reaction mechanism was put forward, and the parameters of HPB nanospheres could be easily adjusted by growth time and template size under optimal water and ethanol ratio. The in vitro tests show the rapid and remarkable photothermal effects of the as-prepared HPB nanospheres under NIR laser irradiation (808 nm). Meanwhile, HPB nanospheres also demonstrated a high DOX loading capacity of 440 mg g-1 as a drug carrier, and the release of the drug can be regulated by the heat from PB shell under the exposure of an NIR laser. The in vivo experiments confirmed the outstanding performance of HPB nanospheres in photothermal/chemo-synergistic therapy of cancer. Conclusion: A solvent-mediated template route was developed to synthesize hollow Prussian blue (HPB) nanospheres in a simple and controllable way. The in vitro and in vivo results demonstrate the as-synthesized HPB nanospheres as a promising candidate due to their low toxicity and high efficiency for cancer therapy.


Assuntos
Portadores de Fármacos/química , Ferrocianetos/química , Nanosferas/química , Fototerapia/métodos , Terapia Combinada , Doxorrubicina/química , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Compostos Férricos/química , Humanos , Hipertermia Induzida
9.
Int J Nanomedicine ; 15: 5545-5559, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32848387

RESUMO

Introduction: Although carbon nanospheres (CNPs) are promising nanomaterials in cancer treatment, how they affect prostate cancer (PCa) remains unclear. Methods: In this study, scanning electron microscopy (SEM), X-ray diffraction (XRD), and Raman spectroscopy were used to confirm the successful synthesis of CNPs. CCK-8, flow cytometry, Transwell, wound healing, Western blot and immunohistochemistry (IHC) assays were performed to evaluate the antitumor effect of CNPs toward the two kinds of prostate cancer cell lines PC3 and DU145. Results: Our results showed that CNPs inhibited cell growth, invasion, and migration and induced apoptosis and autophagy in PCa cells. Multifactor detection of a single Akt phosphorylation pathway and Western blot results suggested the suppression of 4E-BP1 in PCa cells after incubation with CNPs. The results from animal experiments also suggested the antitumor effect of CNPs and reduced 4E-BP1 expression in PCa tissue samples from BALB/c nude mice administered a local subcutaneous injection of CNPs.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Antineoplásicos/química , Antineoplásicos/farmacologia , Carbono/farmacologia , Proteínas de Ciclo Celular/metabolismo , Nanosferas/química , Neoplasias da Próstata/tratamento farmacológico , Animais , Autofagia/efeitos dos fármacos , Carbono/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Microscopia Eletrônica de Varredura , Nanosferas/uso terapêutico , Fosforilação/efeitos dos fármacos , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Análise Espectral Raman , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Int J Nanomedicine ; 15: 4063-4078, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32606664

RESUMO

Background: Among various theories for the origin of cancer, the "stemness phenotype model" suggests a dynamic feature for tumor cells in which non-cancer stem cells (non-CSCs) can inter-convert to CSCs. Differentiation with histone-deacetylase inhibitor, vorinostat (SAHA), can induce stem cells to differentiate as well as enforces non-CSCs to reprogram to CSCs. To avoid this undesirable effect, one can block the Wnt-ßcatenin pathway. Thus, a dual delivery system of SAHA and a Wnt-ßcatenin blocker will be beneficial in the induction of differentiation of CSCs. Protein corona (PC) formation in nanoparticle has a biologic milieu, and despite all problematic properties, it can be employed as a medium for dual loading of the drugs. Materials and Methods: We prepared sphere gold nanoparticles (GNPs) with human plasma protein corona loaded with SAHA as differentiating agent and PKF118-310 (PKF) as a Wnt-ßcatenin antagonist. The MCF7 breast cancer stem cells were treated with NPs and the viability and differentiation were evaluated by Western blotting and sphere formation assay. Results: We found that both drugs loaded onto corona-capped GNPs had significant cytotoxicity in comparison to bare GNP-corona. Data demonstrated an increase in stem cell population and upregulation of mesenchymal marker, Snail by SAHA-loaded GNPs treatment; however, the combination of PKF loaded GNPs along with SAHA-loaded GNPs resulted in a reduction of stem cell populations and Snail marker. We have shown that in MCF7 and its CSCs simultaneous treatment with SAHA and PKF118-310 induced differentiation and inhibition of Snail induction. Conclusion: Our study reveals the PC-coated GNPs as a biocompatible career for both hydrophilic (PKF) and hydrophobic (SAHA) agents which can decrease breast cancer stem cell populations along with reduced stemness state regression.


Assuntos
Neoplasias da Mama/patologia , Carcinogênese/patologia , Ouro/química , Nanopartículas Metálicas/química , Células-Tronco Neoplásicas/patologia , Coroa de Proteína/química , Vorinostat/farmacologia , Proteínas Wnt/antagonistas & inibidores , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinogênese/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Endocitose/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Humanos , Células MCF-7 , Nanosferas/química , Células-Tronco Neoplásicas/efeitos dos fármacos , Espectrofotometria Ultravioleta , Proteínas Wnt/metabolismo , beta Catenina/antagonistas & inibidores , beta Catenina/metabolismo
11.
J Chromatogr A ; 1625: 461343, 2020 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-32709308

RESUMO

A simple magnetic dispersive solid-phase extraction (MDSPE) methodology based on mesoporous Fe3O4@ succinic acid nanospheres and high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) has been developed to determine kanamycin (KNM) and neomycin (NEO) contents in Measles, Mumps, and Rubella (MMR) vaccine products. The monodispersed mesoporous Fe3O4 nanospheres with self-assembled carboxyl terminated shell have been prepared via a simple solvothermal method. These as-synthesized mesoporous Fe3O4 nanospheres showed a high magnetic saturation value (Ms = 46 emu g-1) and large specific surface area (111.12 m2 g-1) which made them potential candidates as sorbents in magnetic solid-phase extraction. The adsorption experimental data fitted well with the Freundlich-Langmuir isotherm and followed a pseudo-second-order kinetic model. Moreover influential parameters on extraction efficiency were investigated and optimized. Under optimal conditions, the limits of detection for KNM and NEO were 1.0 and 0.1 ng mL-1, respectively. Recovery assessments using real samples exhibited recoveries in the range of 96.0 ± 4.3 to 101.5 ± 7.1 %, with relative standard deviations of <10.7% (for intra- day) and <14.6% (for inter- day). The proposed method was successfully applied for different spiked and un-spiked MMR vaccine samples. The presented extraction method provides a fast, selective, robust and practical platform for the detection of KNM and NEO in MMR vaccine samples.


Assuntos
Dextranos/química , Canamicina/análise , Nanopartículas de Magnetita/química , Vacina contra Sarampo/análise , Caxumba/imunologia , Nanosferas/química , Neomicina/análise , Vacina contra Rubéola/análise , Espectrometria de Massas em Tandem/métodos , Adsorção , Cromatografia Líquida de Alta Pressão , Concentração de Íons de Hidrogênio , Cinética , Limite de Detecção , Magnetismo , Nanosferas/ultraestrutura , Reprodutibilidade dos Testes , Extração em Fase Sólida , Solventes/química , Espectroscopia de Infravermelho com Transformada de Fourier , Ácido Succínico/química , Fatores de Tempo , Água/química
12.
J Chromatogr A ; 1624: 461217, 2020 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-32540067

RESUMO

A mesoporous covalent organic polymer (COP) was synthesized through a facile Friedel-Crafts condensation between p-quaterphenyl and trimesoyl chloride, which was designated as COP-QP-TC. Featured with hollow nanospheres architecture, permanent mesoporosity (2.54 nm), large surface area (536 m2 g-1), as well as high thermal and chemical stability, the newly-synthesized COP-QP-TC was utilized as a solid-phase microextraction (SPME) coating for the effective preconcentration of some polycyclic aromatic hydrocarbons (PAHs) and their nitrated and oxygenated derivatives. Combined with gas chromatography-mass spectrometric (GC-MS) detection, the COP-QP-TC based SPME method exhibited high enrichment factors (248-799), low limits of detection (1.31-3.00 ng L-1), good linear range (4.37- 500 ng L-1) and acceptable precisions (relative standard deviations <10.3%). The COP-QP-TC was successfully applied for the SPME of some PAHs and their derivatives from environmental water samples with good method recoveries ranging from 85.8% to 114.4%.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Nanosferas/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Polímeros/química , Limite de Detecção , Hidrocarbonetos Policíclicos Aromáticos/química , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Porosidade , Microextração em Fase Sólida , Poluentes Químicos da Água/análise
13.
Int J Nanomedicine ; 15: 2903-2920, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32425523

RESUMO

Background: The development of highly efficient nanoparticles to convert light to heat for anti-cancer applications is quite a challenging field of research. Methods: In this study, we synthesized unique pimpled gold nanospheres (PGNSs) for plasmonic photothermal therapy (PPTT). The light-to-heat conversion capability of PGNSs and PPTT damage at the cellular level were investigated using a tissue phantom model. The ability of PGNSs to induce robust cellular damage was studied during cytotoxicity tests on colorectal adenocarcinoma (DLD-1) and fibroblast cell lines. Further, a numerical model of plasmonic (COMSOL Multiphysics) properties was used with the PPTT experimental assays. Results: A low cytotoxic effect of thiolated polyethylene glycol (SH-PEG400-SH-) was observed which improved the biocompatibility of PGNSs to maintain 89.4% cell viability during cytometry assays (in terms of fibroblast cells for 24 hrs at a concentration of 300 µg/mL). The heat generated from the nanoparticle-mediated phantom models resulted in ΔT=30°C, ΔT=23.1°C and ΔT=21°C for the PGNSs, AuNRs, and AuNPs, respectively (at a 300 µg/mL concentration and for 325 sec). For the in vitro assays of PPTT on cancer cells, the PGNS group induced a 68.78% lethality (apoptosis) on DLD-1 cells. Fluorescence microscopy results showed the destruction of cell membranes and nuclei for the PPTT group. Experiments further revealed a penetration depth of sufficient PPTT damage in a physical tumor model after hematoxylin and eosin (H&E) staining through pathological studies (at depths of 2, 3 and 4 cm). Severe structural damages were observed in the tissue model through an 808-nm laser exposed to the PGNSs. Conclusion: Collectively, such results show much promise for the use of the present PGNSs and photothermal therapy for numerous anti-cancer applications.


Assuntos
Nanosferas/química , Nanosferas/uso terapêutico , Fototerapia/métodos , Adenocarcinoma/patologia , Adenocarcinoma/terapia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Colorretais/patologia , Neoplasias Colorretais/terapia , Fibroblastos , Ouro/química , Humanos , Lasers , Neoplasias/terapia , Imagens de Fantasmas , Polietilenoglicóis/química
14.
Int J Nanomedicine ; 15: 2685-2697, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32368049

RESUMO

Background: Nanocarriers could deliver significantly higher amounts of antigen to antigen-presenting cells (APCs), which have great potential to stimulate humoral and cellular response in cancer immunotherapy. Thereafter, silica solid nanosphere (SiO2) was prepared, and a model antigen (ovalbumin, OVA) was covalently conjugated on the surface of SiO2 to form nanovaccine (OVA@SiO2). And the application of OVA@SiO2 for cancer immunotherapy was evaluated. Materials and Methods: SiO2 solid nanosphere was prepared by the Stöber method, then successively aminated by aminopropyltriethoxysilane and activated with glutaraldehyde. OVA was covalently conjugated on the surface of activated SiO2 to obtain nanovaccine (OVA@SiO2). Dynamic light scattering, scanning electron microscope, and transmission electron microscope were conducted to identify the size distribution, zeta potential and morphology of OVA@SiO2. The OVA loading capacity was investigated by varying glutaraldehyde concentration. The biocompatibility of OVA@SiO2 to DC2.4 and RAW246.7 cells was evaluated by a Cell Counting Kit-8 assay. The uptake of OVA@SiO2 by DC2.4 and its internalization pathway were evaluated in the absence or presence of different inhibitors. The activation and maturation of bone marrow-derived DC cells by OVA@SiO2 were also investigated. Finally, the in vivo transport of OVA@SiO2 and its toxicity to organs were appraised. Results: All results indicated the successful covalent conjugation of OVA on the surface of SiO2. The as-prepared OVA@SiO2 possessed high antigen loading capacity, which had good biocompatibility to APCs and major organs. Besides, OVA@SiO2 facilitated antigen uptake by DC2.4 cells and its cytosolic release. Noteworthily, OVA@SiO2 significantly promoted the maturation of dendritic cells and up-regulation of cytokine secretion by co-administration of adjuvant CpG-ODN. Conclusion: The as-prepared SiO2 shows promising potential for use as an antigen delivery carrier.


Assuntos
Antígenos/metabolismo , Vacinas Anticâncer/farmacologia , Imunoterapia/métodos , Nanosferas/química , Ovalbumina/química , Adjuvantes Imunológicos/administração & dosagem , Animais , Apresentação do Antígeno , Antígenos/administração & dosagem , Antígenos/química , Antígenos/imunologia , Vacinas Anticâncer/administração & dosagem , Vacinas Anticâncer/química , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Nanosferas/administração & dosagem , Oligodesoxirribonucleotídeos/administração & dosagem , Ovalbumina/imunologia , Ovalbumina/farmacocinética , Células RAW 264.7 , Dióxido de Silício/química
15.
Mikrochim Acta ; 187(5): 273, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32296959

RESUMO

Based on the inner filter effect mechanism of quantum dots, a ratiometric fluorescence nanoprobe was constructed for the determination of Pb(II) ion. Green emitting quantum dots conjugated with DNA substrate (DNA2) acted as donors providing green fluorescence, while gold nanoparticles coupled with DNA enzyme (DNA1) as acceptors quench the green fluorescence. Meanwhile, Fe3O4 nanosphere served as magnetic substrates to facilitate separation process and red fluorescence as an "inner rule" to eliminate the background signal. In the presence of Pb(II) ion, the DNA1 specifically recognize and capture Pb(II) ion with enhanced catalytic activity, which can cleave DNA2 and "turn on" the green fluorescence (I540), while the red fluorescence (I630) remained unchanged. In this way, the ratio of I540/I630 reflects the Pb(II) ion in the system, enabling the quantitative and selective determination of Pb(II) ion over nine different metal ions. Under optimal conditions, the ratiometric fluorescence assay showed good linearity (R2 = 0.98) within the range 10 to 100 ng mL-1. The limit of detection (LOD) was calculated to be 1.79 pg mL-1 (S/N = 3, n = 3, ±3.8%). The proposed fluorescence nanoprobe provides better sensitivity and accuracy than non-ratiometric signal evaluation for Pb(II) ion determination. Schematic representation of ratiometric fluorescence nanoprobe for Pb(II) ion detection using green fluorescence of I540 as "signal switch" and red fluorescence of I630 as "inner rule." Graphical abstract.


Assuntos
DNA Catalítico/química , Chumbo/análise , Nanopartículas de Magnetita/química , Nanosferas/química , Pontos Quânticos/química , Espectrometria de Fluorescência/métodos , Compostos de Cádmio/química , Clivagem do DNA/efeitos dos fármacos , Corantes Fluorescentes/química , Contaminação de Alimentos/análise , Ouro/química , Limite de Detecção , Compostos de Selênio/química , Sulfetos/química , Chá/química , Compostos de Zinco/química
16.
Talanta ; 214: 120864, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32278408

RESUMO

In this work, Fe3O4/N co-doped hollow carbon spheres (Fe3O4@NHCS) as a promising electrocatalysis material had been prepared through carbonizing covalent organic frameworks and ferric irons. The morphology, structure, composition and electrocatalytic performance of Fe3O4@NHCS were characterized by various techniques. The electrode modified with Fe3O4@NHCS (Fe3O4@NHCS/GCE) exhibited excellent electrocatalytic activity for the oxidation of dopamine, uric acid, guanine and adenine. Simultaneous determination of these biomolecules was successfully achieved with Fe3O4@NHCS/GCE. Under the optimum conditions, the linear ranges for the determination of dopamine, uric acid, guanine and adenine were 0.01-40, 0.10-40, 0.50-30 and 0.50-40 µmol/L with the correlation coefficients of 0.9905, 0.9906, 0.9919 and 0.9908, respectively. The detection limits were 6.3, 36.1, 143.2 and 123.5 nmol/L for dopamine, uric acid, guanine and adenine, respectively (S/N = 3). In addition, the modified electrode was also applied to the simultaneous determination of these biomolecules in human serum samples and the recovery were varied from 97.6% to 104.2%. The results demonstrated that the Fe3O4@NHCS modified electrode had the characteristics of high sensitivity, good selectivity and reliability.


Assuntos
Adenina/sangue , Dopamina/sangue , Guanina/sangue , Estruturas Metalorgânicas/química , Ácido Úrico/sangue , Técnicas Biossensoriais , Carbono/química , Técnicas Eletroquímicas , Eletrodos , Compostos Férricos/química , Humanos , Nanosferas/química , Tamanho da Partícula , Propriedades de Superfície
17.
J Nanobiotechnology ; 18(1): 55, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32228604

RESUMO

BACKGROUND: Psoriasis is a malignant skin disease characterized as keratinocyte hyperproliferation and aberrant differentiation. Our previous work reported that a bibenzyl compound, erianin, has a potent inhibitory effect on keratinocyte proliferation. To improve its poor water-solubility, increase anti- proliferation activity, and enhance the skin delivery, erianin loaded dendritic mesoporous silica nanospheres (E/DMSNs) were employed. RESULTS: In this work, DMSNs with pore size of 3.5 nm (DMSN1) and 4.6 nm (DMSN2) were fabricated and E/DMSNs showed pore-size-dependent, significantly stronger anti-proliferative and pro-apoptotic effect than free erianin on human immortalized keratinocyte (HaCaT) cells, resulting from higher cellular uptake efficiency. In addition, compared to free erianin, treatment with E/DMSNs was more effective in reducing mitochondrial membrane potential and increasing cytoplasmic calcium levels, which were accompanied by regulation of mitochondria and endoplasmic reticulum stress (ERS) pathway. Porcine skin was utilized in the ex vivo accumulation and permeation studies, and the results indicated higher drug retention and less drug penetration in the skin when administered as the E/DMSNs-loaded hydrogel compared to the erianin-loaded hydrogel. Conlusions This work not only illustrated the further mechanisms of erianin in anti-proliferation of HaCaT cells but also offer a strategy to enhance the efficiency of erianin and the capacity of skin delivery through the DMSNs drug delivery systems.


Assuntos
Apoptose/efeitos dos fármacos , Bibenzilas/farmacologia , Nanosferas/química , Fenol/farmacologia , Dióxido de Silício/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular , Portadores de Fármacos/farmacologia , Sistemas de Liberação de Medicamentos , Humanos , Queratinócitos/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Pele/efeitos dos fármacos , Neoplasias Cutâneas/tratamento farmacológico , Solubilidade
18.
Mikrochim Acta ; 187(4): 216, 2020 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-32162013

RESUMO

An integrated electrochemical immunoassay is described for the determination of circulating tumor cells (CTCs). For the first time, Ketjen black (KB), which is a superconductive carbon material, was incorporated with Au nanoparticles (AuNPs) and used to modify the surface of gold electrodes. A cocktail of anti-epithelial cell adhesion molecules (EpCAM) and anti-vimentin antibodies was chosen to capture the CTCs. Palladium-iridium-boron-phosphorus alloy-modified mesoporous nanospheres (PdIrBPMNS) served as a catalytic tag to amplify the current signal. Glycine-HCl (Gly-HCl) was used as an antibody eluent to release and collect the captured CTCs from the electrodes for further clinical research without compromising cell viability. The response of the method increased linearly from 10 to 1 × 106 cells mL-1 CTCs, while the detection limit was calculated to be as low as 2 cells mL-1. This method was successfully used to determine CTCs in spiked blood samples and demonstrated good recovery. Graphical abstractKetjen black/AuNPs was incorporated in the electrochemical platform to enhance the electron transfer ability of the electrode surface. PdIrBP mesoporous nanospheres were used to amplify DPV signal in this assay. The introduction of Gly-HCl realized nondestructive recovery of circulating tumor cells.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Nanosferas/química , Células Neoplásicas Circulantes/patologia , Fuligem/química , Boro/química , Condutividade Elétrica , Humanos , Irídio/química , Paládio/química , Tamanho da Partícula , Fósforo/química , Porosidade , Propriedades de Superfície , Células Tumorais Cultivadas
19.
Talanta ; 212: 120764, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32113537

RESUMO

A magnetic-separation-dual-targets fluorescent biosensor was fabricated to detect terminator nopaline synthase (TNOS) and promoter of cauliflower mosaic virus 35s (P35S) in transgenic soybean based on incorporation of bicolor CdTe quantum dots carried by silica nanospheres. In this protocol, the fixed probes for TNOS or P35S were magnetized firstly with Fe3O4@Au magnetic nanosphere by Au-S covalent bonding to achieve magnetized probes. Meanwhile, the capture probes for TNOS or P35S were functionalized with green or red fluorescent microspheres respectively to obtain fluorescently-labeled probes, which could emit relative strong green or red fluorescent signal. Two terminals of TNOS or P35S were recognized by magnetized probes and fluorescently-labeled probes respectively to form the sandwiched structures in the process of biosensor development subsequently, and it was separated by a magnet instantly. The fluorescence intensities of remnant supernatant were measured and analyzed accordingly to achieve simultaneous detection of TNOS and P35S. This biosensor exhibited a good dynamic range, low limit of detection and excellent selectivity in detecting transgenic soybean.


Assuntos
Aminoácido Oxirredutases/genética , Técnicas Biossensoriais/métodos , DNA Viral/análise , Corantes Fluorescentes/química , Nanosferas/química , Proteínas Virais/genética , Compostos de Cádmio/química , Caulimovirus/química , Caulimovirus/enzimologia , Sondas de DNA/química , Sondas de DNA/genética , DNA Viral/genética , Óxido Ferroso-Férrico/química , Ouro/química , Limite de Detecção , Hibridização de Ácido Nucleico , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas , Pontos Quânticos/química , Reprodutibilidade dos Testes , Soja , Telúrio/química
20.
J Phys Chem Lett ; 11(7): 2717-2723, 2020 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-32146808

RESUMO

Functionalized gold nanoparticles are investigated by density functional theory calculations in the context of cancer radiotherapy. Several typical experimental shapes, including nanostars, nanospheres, and nanorods, are modeled by optimizing Au clusters covered by organic monolayers composed of hydrated short-chain polyethylene glycol (PEG) ligands. The PEGylation stabilizes significantly the stellation of decahedral Au54 by deforming significantly its geometry at the spikes. The higher stability of the PEG molecules adsorbed on this stellated nanocluster with respect to the more spherical icosahedral Au55 and truncated octahedral Au79 leads to a larger energy cost to desorb them and thus a weaker propensity for the starred nanoparticle to exchange ligands with the cell membrane, in agreement with experiments. These results open interesting possibilities for advancing our understanding of the cellular uptake of gold nanoparticles.


Assuntos
Nanopartículas Metálicas/química , Polietilenoglicóis/química , Adsorção , Teoria da Densidade Funcional , Ouro/química , Ligantes , Modelos Químicos , Nanosferas/química , Nanotubos/química
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