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1.
Top Curr Chem (Cham) ; 378(1): 12, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31907672

RESUMO

Nanomaterials have revolutionized the sensing and biosensing fields, with the development of more sensitive and selective devices for multiple applications. Gold, silver and iron oxide nanoparticles have played a particularly major role in this development. In this review, we provide a general overview of the synthesis and characteristics of gold, silver and iron oxide nanoparticles, along with the main strategies for their surface functionalization with ligands and biomolecules. Finally, different architectures suitable for electrochemical applications are reviewed, as well as their main fabrication procedures. We conclude with some considerations from the authors' perspective regarding the promising use of these materials and the challenges to be faced in the near future.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Compostos Férricos/síntese química , Ouro/química , Nanopartículas/química , Prata/química , Compostos Férricos/química , Ligantes , Propriedades de Superfície
2.
Chemosphere ; 238: 124690, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31524625

RESUMO

Doxorubicin (DOX) originated from users' urine has been an emerging environmental pollutant due to its significant genotoxicity to mankind. Thus, urine source separation is a potential strategy to isolate DOX at a higher concentration and reduce the burden of downstream wastewater treatment. To develop highly efficient, easy separation and retrievable materials for individual patient to conveniently remove DOX from own urine, magnetic Cu3(PO4)2 nanoflowers were prepared through anchoring amino-functionalized magnetic nanoparticles on the Cu3(PO4)2 nanoflowers. Characterizations revealed the magnetic nanoflowers were spherical in shape with a mean size of 15 µm, and porous and hierarchical in structure. Magnetic nanoparticles located the surface of petals. Multibatch experiments were performed to assess the removal performance of DOX from aqueous solution. The magnetic nanoflowers exhibited excellent removal efficiency of DOX under weakly alkaline condition at ambient temperature. Linear and non-linear analyses were carried out to compare the best fitting kinetics and isotherms. Sorption kinetic data best fitted the pseudo-second order model. The Freundlich isotherm explained equilibrium sorption data with R2 = 0.993 higher than that for the Langmuir isotherm. When the pH of synthetic urine was adjusted to weakly alkaline (pH 8.0-9.0), over 95% of DOX (20 mg L-1) was removed by a little of magnetic nanoflowers (50 mg L-1) within 5 min. Meanwhile, the magnetic nanoflowers could be easily separated and recovered from the synthetic urine by a magnet. So, for individual urine source separation strategy, the magnetic nanoflower seems to be an efficient, convenient and inexpensive approach to remove DOX from human urine.


Assuntos
Cobre/química , Doxorrubicina/análise , Magnetismo/métodos , Urina/química , Purificação da Água/métodos , Adsorção , Humanos , Concentração de Íons de Hidrogênio , Fenômenos Magnéticos , Nanopartículas/química , Fosfatos/química , Águas Residuárias/química
3.
Chemosphere ; 238: 124648, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31524610

RESUMO

Deoxynivalenol (DON) is one of the most globally prevalent mycotoxins mainly produced by Fusarium species. It can cause pollution to water environmental quality due to its water solubility. Therefore, it is necessary to develop a green and efficient detoxification technology for DON. More importantly, the toxicity of the degradation products should be assessed. Photocatalytic degradation technology has attracted increasing attention in the field of pollutants treatment, especially for wastewater treatment. Herein, the as-prepared NaYF4:Yb,Tm@TiO2 composite (UCNP@TiO2) was employed as a novel photocatalyst for the NIR-enhanced photocatalytic degradation of DON. Three intermediate products were identified by using the ESI/MS analysis and secondary mass spectrogram, with the m/z values of 329.399, 311.243 and 280.913, respectively. Furthermore, the in vitro safety of the product mixtures with various degradation time (30 min, 60 min, 90 min and 120 min) were evaluated through the influences on cell viability, cell morphology, cell cycle, intracellular reactive oxygen species (ROS) level, cell apoptosis and antioxidant capacity of HepG2 cells. There were no significant differences in these investigated indicators between the control (free of DON) and 120 min products treatment. Overall, the results indicated that the toxicity of degradation products after 120 min irradiation was much lower and even nontoxic than that of DON.


Assuntos
Micotoxinas/química , Titânio/química , Tricotecenos/química , Purificação da Água/métodos , Sobrevivência Celular/efeitos dos fármacos , Células Hep G2/citologia , Células Hep G2/efeitos dos fármacos , Células Hep G2/metabolismo , Humanos , Micotoxinas/análise , Nanopartículas/química , Espécies Reativas de Oxigênio/metabolismo , Tricotecenos/toxicidade , Águas Residuárias/análise , Águas Residuárias/química , Poluentes da Água/química
4.
J Sci Food Agric ; 100(1): 268-276, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31512249

RESUMO

BACKGROUND: The application of Pickering emulsion stabilized by food-derived particles is of great interest in the food field, including meat processing. However, the creaming phenomenon is a thorny problem and may impact the resulting product quality. Here, we used polysaccharide nanoparticles from Flammulina velutipes (FVPN) as a stabilizer to prepare a oil/water Pickering emulsion and partly replace the original fat of common emulsified sausage, focusing on exploring the influence of phase separation on the sausage's techno-functional and sensory quality, with the aim of developing a new alternative fat substitute. RESULTS: Reformulated sausages showed increases in moisture (53.24-64.85%) and protein content (11.97-12.76%), but were reduced in fat content (27.28-18.76%). The increased FPOE (FVPN-palm oil emulsion; substitution rate 5-37%) amount in sausages resulted in significantly reduced (P < 0.05) cooking loss (18.87-8.63%). Meanwhile, emulsion improved the springiness and cohesiveness of sausage and significantly reduced (P < 0.05) hardness and chewiness when the replacement amount was less than 20%. Experimental sausages attained a more compact pore structure without harming sensory characteristics. Compared with creaming emulsion, pristine emulsion resulted in a sausage with higher moisture content, lower cooking loss, better elasticity and denser structure. CONCLUSION: The characteristics of sausages could be influenced by emulsion stability. Emulsion, especially with no creaming, can be effectively used as fat substitute at a level of 20% or less without adversely affecting the sensory characteristics of emulsified sausages. The incorporation of FPOE provides the potential for developing a new alternative approach for animal fat improvement in meat products. © 2019 Society of Chemical Industry.


Assuntos
Substitutos da Gordura/análise , Flammulina/química , Aditivos Alimentares/análise , Produtos da Carne/análise , Polissacarídeos/análise , Animais , Culinária , Emulsões/química , Manipulação de Alimentos , Dureza , Humanos , Nanopartículas/química , Óleo de Palmeira/análise , Suínos , Paladar , Água/análise
5.
J Sci Food Agric ; 100(2): 570-577, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31588994

RESUMO

BACKGROUND: Among nanomaterials, Ti and ZnO nanoparticles are often chosen as preservation materials because of their antibacterial properties. Chitosan, as a natural biopolymer, has potential because of its abundance, compatibility and antibacterial properties. To improve the physicochemical and preservation properties of in situ SiOx chitosan (CS) composite coating, Ti/ZnO/SiOx CS composite coatings were prepared with Ti-doped ZnO (Ti/ZnO) nanorods and nanoballs. The composite coating structures were characterized by Fourier transform infrared, X-ray diffraction and scanning electron microscopy, and their physicochemical and preservation properties were determined simultaneously. RESULTS: The results show that the Ti/ZnO nanoparticles are beneficial to homogeneous dispersion of in situ synthesized nano SiOx in the CS coating, and that Ti/ZnO nanoballs have better dispersion than Ti/ZnO nanorods. Moreover, strong hydrogen bonds are formed among Ti/ZnO nanoparticles and in situ synthesized nano SiOx and CS molecules, and the primary structure of CS is disorganized. Thereby, the gas permeabilities and mechanical properties of the CS coatings are improved due to modification of Ti/ZnO nanoparticles, and the Ti/ZnO nanoballs/SiOx CS composite coating is optimal. The preservation properties of the CS coatings on Sciaenops ocellatus are significantly improved, and those of Ti/ZnO/in situ SiOx CS composite coatings are superior. CONCLUSION: The preservation properties of the CS composite coatings on S. ocellatus are significant, and the Ti/ZnO nanoballs/SiOx CS composite coating is even better. Therefore, the co-modification method of in situ nanoparticles and antibacterial nanoparticles may be a promising method to improve the preservation properties of CS coatings. © 2019 Society of Chemical Industry.


Assuntos
Antibacterianos/química , Quitosana/química , Titânio/química , Óxido de Zinco/química , Nanopartículas/química , Difração de Raios X
6.
J Agric Food Chem ; 68(2): 603-611, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31860287

RESUMO

Mixed Pickering emulsions were prepared by blending anionic nanocellulose-stabilized lipid droplets with cationic nanochitin-stabilized lipid droplets. Changes in the surface potential, particle size, shear viscosity, and morphology of the mixed emulsions were characterized when the droplet mixing ratio was varied. Emulsion properties could be tailored by altering the pH and mixing ratio. Surface potential measurements suggested that the nanochitin-coated lipid droplets adsorbed to the surfaces of the nanocellulose-coated lipid droplets, thereby dominating the overall electrical characteristics of the mixed emulsions. As a result, the mixed emulsions had better stability to coalescence than the single emulsions containing only nanocellulose-coated lipid droplets. Our results suggest that the physicochemical properties, shelf life, and functional performance of Pickering emulsions may be modulated by blending different kinds of particle-stabilized lipid droplets together.


Assuntos
Celulose/química , Quitina/química , Emulsões/química , Gotículas Lipídicas/química , Adsorção , Concentração de Íons de Hidrogênio , Nanopartículas/química , Tamanho da Partícula , Viscosidade
7.
J Agric Food Chem ; 68(2): 652-659, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31869222

RESUMO

Casein phosphopeptides are known to enhance zinc absorption, but the underlying mechanism remains unclear. Here, a gastrointestinal casein hydrolysate (CH) was found to keep zinc in solution despite heavy precipitation of calcium and phosphate, the omnipresent mineral nutrients that could co-precipitate zinc out of solution instantly and almost completely under physiologically relevant conditions. Dynamic light scattering, transmission electron microscopy, and energy-dispersive X-ray analysis displayed the CH-mediated formation of zinc/calcium phosphate (Zn/CaP) nanocomplexes aggregated from rather small nanoclusters. The ex vivo mouse ileal loop experiments revealed enhanced intestinal zinc absorption by CH's prevention of zinc co-precipitation with CaP, and the treatments with specific inhibitors unveiled the involvement of macropinocytic internalization, lysosomal degradation, and transcytosis in the intestinal uptake of zinc from Zn/CaP nanocomplexes. A low calcium-to-phosphorus ratio adversely affected CH's efficiency to enhance zinc solubility and absorption. Overall, our study provides a new paradigm for casein phosphopeptides to improve zinc bioavailability.


Assuntos
Fosfatos de Cálcio/química , Caseínas/química , Intestino Delgado/metabolismo , Zinco/química , Zinco/metabolismo , Animais , Disponibilidade Biológica , Fosfatos de Cálcio/metabolismo , Caseínas/metabolismo , Absorção Intestinal , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nanopartículas/química , Nanopartículas/metabolismo
8.
J Colloid Interface Sci ; 559: 51-64, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31610305

RESUMO

Aiming at the inefficiency and toxicity in traditional antitumor therapy, a novel multifunctional nanoplatform was constructed based on hollow mesoporous carbon (HMC) to achieve triple stimuli response and dual model antitumor therapy via chemo-photothermal synergistic effect. HMC was used as an ideal nanovehicle with a high drug loading efficiency as well as a near-infrared (NIR) photothermal conversion agent for photothermal therapy. Acid-dissoluble, luminescent ZnO quantum dots (QDs) were used as the proper sealing agents for the mesopores of HMC, conjugated to HMC via disulfide linkage to prevent drug (doxorubicin, abbreviated as Dox) premature release from Dox/HMC-SS-ZnO. After cellular endocytosis, the Dox was released in a pH, GSH and NIR laser triple stimuli-responsive manner to realize accurate drug delivery. Moreover, the local hyperthermia effect induced by NIR irradiation could promote the drug release, enhance cell sensitivity to chemotherapeutic agents, and also directly kill cancer cells. As expected, Dox/HMC-SS-ZnO exhibited a high drug loading capacity of 43%, well response to triple stimuli and excellent photothermal conversion efficiency η of 29.7%. The therapeutic efficacy in 4T1 cells and multicellular tumor spheroids (MCTSs) demonstrated that Dox/HMC-SS-ZnO + NIR had satisfactory chemo-photothermal synergistic effect with a combination index (CI) of 0.532. The cell apoptosis rate of the combined treatment group was more than 95%. The biodistribution and pharmacodynamics studies showed its biosecurity to normal tissues and synergistic inhibition effect to tumor cells. These distinguished results indicated that the Dox/HMC-SS-ZnO nanoplatform is potential to realize efficient triple stimuli-responsive drug delivery and dual model chemo-photothermal synergistic antitumor therapy.


Assuntos
Antineoplásicos/química , Carbono/química , Terapia Combinada/métodos , Portadores de Fármacos/química , Nanopartículas/química , Pontos Quânticos/química , Óxido de Zinco/química , Animais , Antineoplásicos/farmacocinética , Apoptose/efeitos dos fármacos , Materiais Biocompatíveis/química , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Liberação Controlada de Fármacos , Corantes Fluorescentes/química , Humanos , Raios Infravermelhos , Camundongos Endogâmicos BALB C , Fototerapia/métodos , Porosidade , Propriedades de Superfície , Distribuição Tecidual , Óxido de Zinco/farmacocinética
9.
J Colloid Interface Sci ; 559: 197-205, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31627143

RESUMO

Mesoporous silica nanoparticle (MSN) demonstrates great potentials as a loading platform for bactericidal agents, but may be limited by its application form of bulk or powder. Herein, we developed MSN surface-enriched composite membranes with remarkable photodynamic antimicrobial activities via a facile electrospinning method. The mixture of zein and polycaprolactone (PCL) was served as the polymeric matrix, while the methylene blue (MB) loaded MSN was modified by trichloro (1H, 1H, 2H, 2H-heptadecafluorodecyl) silane (THFS) and acted as reactive oxygen species (ROS) generator to exert their antimicrobial performances. Owing to its low surface energy, the fluorinated MSN tended to be enriched on the surface of the nanofiber, hence significantly enhancing the ROS generation. Moreover, benefiting from the surface enrichment of the fluorinated nanoparticles, the composite membrane displayed obvious surface hydrophobicity and exhibited discernible bacterial repellency. Subsequently, upon visible light (660 nm) irradiation, the composite membrane demonstrated remarkable photodynamic antibacterial activities against Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli) but without essential detrimental impacts on the mammalian cells. We envision that this self-enriched MSN composite membrane may find broad applications in bacterial infection-resistant areas.


Assuntos
Anti-Infecciosos/química , Azul de Metileno/química , Nanopartículas/química , Fotoquimioterapia/métodos , Dióxido de Silício/química , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Fibroblastos/citologia , Flúor/química , Interações Hidrofóbicas e Hidrofílicas , Luz , Camundongos , Poliésteres/química , Porosidade , Espécies Reativas de Oxigênio/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Propriedades de Superfície , Zeína/química
10.
Food Chem ; 307: 125523, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31639572

RESUMO

Lutein is a bioactive found in dark leafy vegetables that may be used as a nutraceutical agent in foodstuff and an inhibitor of key enzymes of the human body such as those involved in the cholinergic system. However, its high hydrophobicity leads to low bioavailability and must be overcome if lutein is to be added in foods. The objective of this study was to evaluate the influence of nanoencapsulated lutein in the activity of the acetylcholinesterase enzyme. The in vitro study was carried out using water in order to evaluate the impact of encapsulation on the hydrophilicity of lutein. In vitro assays showed that lutein, both free and nanoencapsulated, presented a mixed-type inhibition behavior, and encapsulated lutein was able to inhibit acetylcholinesterase activity even in an aqueous medium. Inhibition was also showed by the in silico docking results which show that lutein interacted with the pocket region of the enzyme.


Assuntos
Acetilcolinesterase/metabolismo , Cápsulas/química , Luteína/química , Simulação de Acoplamento Molecular , Nanopartículas/química , Acetilcolinesterase/química , Sítios de Ligação , Suplementos Nutricionais/análise , Humanos , Interações Hidrofóbicas e Hidrofílicas , Cinética , Luteína/metabolismo , Estrutura Terciária de Proteína
11.
Bioelectrochemistry ; 131: 107392, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31707277

RESUMO

A flexible acetylcholinesterase (AChE) film biosensor, based on a AuNPs-MoS2-reduced graphene oxide/polyimide flexible film (rGO/PI) electrode, has been synthesized for paraoxon detection. In this study, the rGO/PI film acts as the flexible substrate and AuNPs are reduced by monolayer MoS2 under illumination. Transmission electron microscopy revealed that AuNPs are uniformly dispersed on the MoS2-rGO/PI electrode surface with a diameter ~10nm. X-ray photoelectron spectroscopy indicated that a strong binding force exists between reduced AuNPs and monolayer MoS2. The AChE modified AuNPs-MoS2-rGO/PI flexible film biosensor is used to hydrolyze acetylcholine chloride and obtain a large current response at 0.49V by differential pulse voltammetry, demonstrating successful immobilization of AChE. In view of the inhibition of paraoxon on the AChE, under optimal conditions, the AChE/AuNPs-MoS2-rGO/PI film biosensor shows a linear response over a concentration range 0.005-0.150µg/mL, a sensitivity of 4.44 uA/µg/mL, a detection limit of 0.0014µg/mL, acceptable reproducibility and stability to paraoxon. The flexible film biosensor has also proved used for detection of paraoxon in real samples.


Assuntos
Acetilcolinesterase/metabolismo , Técnicas Biossensoriais , Dissulfetos/química , Ouro/química , Grafite/química , Inseticidas/análise , Molibdênio/química , Nanopartículas/química , Paraoxon/análise , Limite de Detecção
12.
Ultrasonics ; 101: 106033, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31561207

RESUMO

The objective of this study was to use ultrasound in combination with nanoparticulate formulations of taxane drugs for an additive approach to overcome multidrug resistance (MDR). Polymeric nanoparticulate formulations containing both chemotherapeutic taxane drugs and a polymeric inhibitor (MePEG17-b-PCL5) of drug resistant proteins have been previously developed in an attempt to overcome MDR in cells. High frequency (>1 MHz) ultrasound has been shown to increase the uptake of cytotoxic drugs in MDR proliferating cells and has been suggested as a different way to overcome MDR, resensitize drug resistant cancer cells and allow for chemotherapeutic efficacy. MDCK-MDR cells were incubated with docetaxel (DTX) or paclitaxel (PTX) loaded, solid core, nanoparticles made from a 50:50 ratio of two diblock copolymers, MePEG114-b-PCL200 and MePEG17-b-PCL5 (PCL200/PCL5). The accumulation of drug in MDCK-MDR cells was measured using radiolabeled drug and the viability of cells was determined using an MTS cell proliferation assay. The effect of ultrasound (4 MHz, 32 W/cm2, 10 s, 25% duty cycle) on drug uptake and cell viability was studied. Using free DTX or PTX, MDCK-MDR cells were killed at sublethal doses of drug with the P-gp inhibitor (MePEG17-b-PCL5) present at a concentration of just 0.006% (m/v) and cell death began after just 3 h of incubation. Using sublethal incubation doses of PTX or DTX in PCL200/PCL5 nanoparticles for 90 min, followed by a second exposure to blank PCL200/PCL5 nanoparticles, cell viability dropped by approximately 60% at 24 h. Drug accumulation increased by 1.43-1.9 fold following five bursts of ultrasound applied at 90 min. Both, increased ultrasound exposure and increased concentrations of blank nanoparticles during the second incubation allowed for increased levels of cell death. The combined use of ultrasound with taxane and P-gp inhibitor loaded polymeric nanoparticles may allow for increased accumulation of drug and inhibitor which may then release both agents inside cells in a controlled manner to overcome drug resistance in MDR cells.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Antineoplásicos Fitogênicos/farmacologia , Docetaxel/farmacologia , Nanopartículas/química , Paclitaxel/farmacologia , Polietilenoglicóis/farmacologia , Ondas Ultrassônicas , Animais , Antineoplásicos Fitogênicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Docetaxel/química , Cães , Sistemas de Liberação de Medicamentos , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Paclitaxel/química , Polietilenoglicóis/química , Polímeros/química , Polímeros/farmacologia , Células Tumorais Cultivadas
13.
J Colloid Interface Sci ; 558: 137-144, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31586733

RESUMO

Platinum oxide (PtOx) nanoparticles (NPs) have been shown to possess anticancer activity by releasing ionic Pt species under biological conditions. However, the dissolution kinetics and the changes in the chemical state of Pt during PtOx dissolution have not yet been studied. To fill this gap, we prepared a composite (designated as PtOx@MMT-2) containing PtOx NPs on hollow mesoporous silica nanospheres and studied the dissolution of the material in different biorelevant media. We found that the release of Pt was retarded due to the adsorption of biomolecules on PtOx NPs during the degradation of host silica. The biomolecules adsorption also lowered the accessibility of PtOx NPs, resulting in the reduced catalase-like activity of the NPs. In line with the results, the cytotoxicity of PtOx@MMT-2, which was positively correlated to the amount of Pt uptake, was reduced by biomolecules adsorption. Our findings should be applicable to other metal (oxide) NPs under biological conditions and may provide implications for the design of nanomaterials for practical therapeutic applications.


Assuntos
Materiais Biocompatíveis/química , Nanopartículas/química , Óxidos/química , Platina/química , Dióxido de Silício/química , Adsorção , Materiais Biocompatíveis/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células HeLa , Humanos , Nanopartículas/uso terapêutico , Solubilidade
14.
Chemosphere ; 240: 124884, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31542586

RESUMO

Antibiotics and heavy metals are frequently detected simultaneously in water environment. In this study, the competitive adsorption behavior of tylosin (TYL) and sulfamethoxazole (SMX) on nano-hydroxyapatite modified biochar (nHAP@biochar) in accordance with Cu(II) in single, binary and ternary systems was investigated. The specific surface area of nHAP@biochar was 566.056 m2/g. The adsorption of TYL on nHAP@biochar reduced by 13.36%-41.04% or 9.92%-38.69% with Cu(II) and SMX in the solution, respectively. The suppression of SMX was stronger than Cu(II) on the adsorption of TYL when the SMX or Cu(II) was constant. The adsorption of SMX increased by 2.01-3.56 times in the present of Cu(II), while suppressed by TYL up to 42.30%. Due to the bridging of TYL or SMX between the nHAP@biochar and Cu(II) and destroying of bound water surrounded, the adsorption of Cu(II) increased to a greater extent. Electrostatic interaction and H-bond were the two main interactions between TYL, SMX and Cu(II) and nHAP@biochar. π-π interactions was also interaction between the SMX and nHAP@biochar.


Assuntos
Carvão Vegetal/química , Cobre/metabolismo , Durapatita/química , Nanopartículas/química , Sulfametoxazol/metabolismo , Tilosina/metabolismo , Poluentes Químicos da Água/metabolismo , Adsorção , Cobre/isolamento & purificação , Sulfametoxazol/isolamento & purificação , Tilosina/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos
15.
Braz Oral Res ; 33: e062, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31859706

RESUMO

Laboratory evidence has demonstrated the antimicrobial effect of Melaleuca alternifolia (MEL) against oral microorganisms. This randomized, double-blind, crossover clinical trial, compared the anti-biofilm and anti-inflammatory effects of MEL nanoparticles with 0.12% chlorhexidine gluconate (CHX) on biofilm-free (BF) and biofilm-covered (BC) surfaces. Before each experimental period, the participants refrained from all oral hygiene practices for 72 hours. The 60 participants were randomly assigned to professional prophylaxis in two quadrants (Q1-Q3 or Q2-Q4), and rinsed with MEL or CHX for four days. The Quigley & Hein plaque index (QHPI), gingival crevicular fluid (GCF) volume, and participants' perceptions were assessed. CHX showed significantly lower mean QHPI on BF (2.65 ± 0.34 vs. 3.34 ± 0.33, p < 0.05) and BC surfaces (2.84 ± 0.37 vs. 3.37 ± 0.33, p < 0.05). Intragroup comparisons indicated reductions in GCF in all the groups, with significant differences only for CHX on BF surfaces (p < 0.05). Intergroup comparisons revealed no significant differences (p > 0.05). Based on individual perceptions, CHX had better taste and biofilm control, but resulted in a greater change in taste. Nevertheless, MEL demonstrated anti-inflammatory effects similar to those of CHX. Further clinical trials testing different protocols, concentrations and follow-up periods are required to establish its clinical application.


Assuntos
Anti-Inflamatórios/farmacologia , Biofilmes/efeitos dos fármacos , Clorexidina/análogos & derivados , Placa Dentária/tratamento farmacológico , Melaleuca/química , Antissépticos Bucais/farmacologia , Nanopartículas/química , Adolescente , Adulto , Clorexidina/farmacologia , Estudos Cross-Over , Índice de Placa Dentária , Método Duplo-Cego , Feminino , Líquido do Sulco Gengival/efeitos dos fármacos , Humanos , Masculino , Higiene Bucal/métodos , Doenças Periodontais/microbiologia , Doenças Periodontais/prevenção & controle , Estatísticas não Paramétricas , Propriedades de Superfície/efeitos dos fármacos , Inquéritos e Questionários , Escala Visual Analógica , Adulto Jovem
17.
Top Curr Chem (Cham) ; 378(1): 2, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31761971

RESUMO

A new field where the utilization of mechanochemistry can create new opportunities is materials chemistry, and, more interestingly, the synthesis of novel nanomaterials. Ball-milling procedures and ultrasonic techniques can be regarded as the most important mechanochemical synthetic tools, since they can act as attractive alternatives to the conventional methods. It is also feasible for the utilization of mechanochemical forces to act synergistically with the conventional synthesis (as a pre-treatment step, or simultaneously during the synthesis) in order to improve the synthetic process and/or the material's desired features. The usage of ultrasound irradiation or ball-milling treatment is found to play a crucial role in controlling and enhancing the structural, morphological, optical, and surface chemistry features that are important for heterogeneous photocatalytic practices. The focus of this article is to collect all the available examples in which the utilization of sonochemistry or ball milling had unique effects as a synthesis tool towards zero- or one-dimensional nanostructures of a semiconductor which is assumed as a benchmark in photocatalysis, titanium dioxide.


Assuntos
Nanopartículas/química , Titânio/química , Catálise , Processos Fotoquímicos
18.
Pharm Res ; 36(12): 174, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31667638

RESUMO

PURPOSE: The overall goal of this study was to investigate the dissolution performance and crystallization kinetics of amorphous solid dispersions (ASDs) of a weakly basic compound, posaconazole, dispersed in a pH-sensitive polymeric matrix consisting of hydroxypropyl methylcellulose acetate succinate (HPMC-AS), using fasted-state simulated media. METHODS: ASDs with three different drug loadings, 10, 25 and 50 wt.%, and the commercially available tablets were exposed to acidic media (pH 1.6), followed by transfer to, and dissolution in, intestinal media (pH 6.5). Parallel single stage dissolution experiments in only simulated intestinal media were also performed to better understand the impact of the gastric stage. Different analytical methods, including nanoparticle tracking analysis, powder x-ray diffraction, second harmonic generation and two-photon excitation ultraviolet fluorescence microscopy, were used to characterize the phase behavior of these systems at different stages of dissolution. RESULTS: Results revealed that all ASDs exhibited some degree of drug release upon suspension in acidic media, and were also vulnerable to matrix crystallization. Upon transfer to intestinal media conditions, supersaturation was observed. This was short-lived for some dispersions due to the release of the crystals formed in the acid immersion stage which acted as seeds for crystal growth. Lower drug loading ASDs also exhibited transient formation of amorphous nanodroplets prior to crystallization. CONCLUSIONS: This work emphasizes the significance of assessing the impact of pH change on dissolution and provides a fundamental basis of understanding the phase behavior kinetics of ASDs of weakly basic drugs when formulated with pH sensitive polymers.


Assuntos
Portadores de Fármacos/química , Metilcelulose/análogos & derivados , Triazóis/química , Cristalização , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Concentração de Íons de Hidrogênio , Cinética , Metilcelulose/química , Nanopartículas/química , Tamanho da Partícula , Transição de Fase , Solubilidade , Temperatura Ambiente
19.
Phys Rev Lett ; 123(15): 158002, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31702313

RESUMO

We study the interplay between a crack tip slowly propagating through a hydrogel and nanoparticles suspended in its liquid environment. Using a proteinic gel enables us to tune the electrostatic interaction between the network and silica colloids. Thereby, we unveil two distinct, local toughening mechanisms. The primary one is charge independent and involves the convective building of a thin particulate clog, hindering polymer hydration in the crack process zone. When particles and network bear opposite charges, transient adhesive bonding superimposes, permitting the remarkable pinning of a crack by a liquid drop.


Assuntos
Biopolímeros/química , Hidrogéis/química , Nanopartículas/química , Colágeno/química , Modelos Químicos , Desnaturação Proteica , Sílica Gel/química , Eletricidade Estática
20.
J Photochem Photobiol B ; 201: 111651, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31683166

RESUMO

Designing biomimetic biomaterials influenced by the common complex structure of hard tissues is yet a test these days. The control of bio-mineralization procedure onto biomaterials should be assessed before the use in medical applications. Coming to the bone rejuvenation applications, this work assessed the in vitro antibacterial activity and interacting between osteoblast cells (MG63) on poly (hydroxypropyl methacrylate) (PHPMA) cryogel consolidated with Zn/Ce substituted hydroxyapatite (MHAp) nanocomposite (PHPMA/MHAp). Osteoblast cell multiplication, morphology, and metabolic action were assessed through various conventions. The functional group, texture, mechanical properties, and protein adsorption profiles of the fabricated nanocomposite were analyzed by the FTIR, XRD, SEM, and mechanical examinations, respectively. The bacterial activity of nanocomposites was additionally assessed against E. coli and S. aureus microorganisms, individually. Nanocomposite advanced endo-chondral ossification at the messed up parts of the bone deformity than cryogel did. These results recommend that PHPMA/MHAp nanocomposites joined the good innate properties of each polymer and bioceramic, giving a mechanically powerful, cell-responsive, and permeable stage for hard tissue applications.


Assuntos
Criogéis/química , Durapatita/química , Fraturas do Fêmur/terapia , Nanocompostos/química , Nanopartículas/química , Animais , Regeneração Óssea/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Cério/química , Modelos Animais de Doenças , Escherichia coli/efeitos dos fármacos , Fraturas do Fêmur/patologia , Nanocompostos/uso terapêutico , Nanocompostos/toxicidade , Polímeros/química , Ratos , Staphylococcus aureus/efeitos dos fármacos , Engenharia Tecidual , Zinco/química
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