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1.
J Nanobiotechnology ; 20(1): 212, 2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35524270

RESUMO

A multifunctional nanoplatform with core-shell structure was constructed in one-pot for the synergistic photothermal, photodynamic, and chemotherapy against breast cancer. In the presence of gambogic acid (GA) as the heat-shock protein 90 (HSP90) inhibitor and the gold nanostars (AuNS) as the photothermal reagent, the assembly of Zr4+ with tetrakis (4-carboxyphenyl) porphyrin (TCPP) gave rise to the nanocomposite AuNS@ZrTCPP-GA (AZG), which in turn, further coated with PEGylated liposome (LP) to enhance the stability and biocompatibility, and consequently the antitumor effect of the particle. Upon cellular uptake, the nanoscale metal - organic framework (NMOF) of ZrTCPP in the resulted AuNS@ZrTCPP-GA@LP (AZGL) could be slowly degraded in the weak acidic tumor microenvironment to release AuNS, Zr4+, TCPP, and GA to exert the synergistic treatment of tumors via the combination of AuNS-mediated mild photothermal therapy (PTT) and TCPP-mediated photodynamic therapy (PDT). The introduction of GA serves to reduce the thermal resistance of the cell to re-sensitize PTT and the constructed nanoplatform demonstrated remarkable anti-tumor activity in vitro and in vivo. Our work highlights a facile strategy to prepare a pH-dissociable nanoplatform for the effective synergistic treatment of breast cancer.


Assuntos
Neoplasias da Mama , Estruturas Metalorgânicas , Nanocompostos , Fotoquimioterapia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Feminino , Humanos , Lipossomos/uso terapêutico , Microambiente Tumoral , Xantonas
2.
Sci Rep ; 12(1): 7316, 2022 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-35513449

RESUMO

In this work, a simple and green synthesis procedure for phytofabrication Zinc oxide-silver supported biochar nanocomposite (Ag/ZnO@BC) via Persicaria salicifolia biomass is investigated for the first time to uphold numerous green chemistry such as less hazardous chemical syntheses. XRD technique showed the crystal structure of the phytosynthesized Ag/ZnO@BC, whereas UV-visible spectroscopy, FT-IR, SEM, EDX, TEM, and XPS analyses indicated the successful biosynthesis of the nanocomposite. Testing the photocatalytic potential of this novel nanocomposite in the removal of TC under different conditions unraveled its powerful photodegradation efficiency that reached 70.3% under the optimum reaction conditions: TC concentration; 50 ppm, pH; 6, a dose of Ag/ZnO@BC; 0.01 g, temperature; 25 °C, and H2O2 concentration; 100 mM. The reusability of Ag/ZnO@BC was evident as it reached 53% after six cycles of regeneration. Ag/ZnO@BC was also shown to be a potent antimicrobial agent against Klebsiella pneumonia as well as a promising antioxidant material. Therefore, the current work presented a novel nanocomposite that could be efficiently employed in various environmental and medical applications.


Assuntos
Nanocompostos , Óxido de Zinco , Antibacterianos/química , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Catálise , Peróxido de Hidrogênio , Nanocompostos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Tetraciclina , Óxido de Zinco/química
3.
J Mol Model ; 28(6): 143, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35543752

RESUMO

Functionalization of graphene is the best way to create a high degree of dispersion and bonding to polymer matrix in order to obtain high performance composites. The effects of carboxyl (-COOH) functionalized graphene (FG) on the mechanical properties of its epoxy-based nanocomposites have been examined by molecular dynamics (MD) simulations. Simulations cells of nanocomposites with varying wt% of FG (1, 2, and 3 wt%) were constructed using Material Studio 6.0. The MD simulation findings of nanocomposites reveal that they have better mechanical properties such as elastic modulus, bulk modulus, shear modulus, and the Poisson's ratio than pure epoxy. Furthermore, the computational results of nanocomposites have been effectively confirmed with available experimental data. Therefore, the current MD simulation shows a decent computational sign for the existing experimental and simulation outcomes on mechanical properties of FG/epoxy nanocomposites.


Assuntos
Grafite , Nanocompostos , Resinas Epóxi , Simulação de Dinâmica Molecular , Polímeros
4.
Sci Rep ; 12(1): 6565, 2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35449436

RESUMO

The study used a one-step hydrothermal method to prepare Fe3O4-FeVO4 and xRGO/Fe3O4-FeVO4 nanocomposites. XRD, TEM, EDS, XPS, DRS, and PL techniques were used to examine the structurally and morphologically properties of the prepared samples. The XRD results appeared that the Fe3O4-FeVO4 has a triclinic crystal structure. Under hydrothermal treatment, (GO) was effectively reduced to (RGO) as illustrated by XRD and XPS results. UV-Vis analysis revealed that the addition of RGO enhanced the absorption in the visible region and narrowed the band gap energy. The photoactivities of the prepared samples were evaluated by degrading methylene blue (MB), phenol and brilliant green under sunlight illumination. As indicated by all the nanocomposites, photocatalytic activity was higher than the pure Fe3O4-FeVO4 photocatalyst, and the highest photodegradation efficiency of MB and phenol was shown by the 10%RGO/Fe3O4-FeVO4. In addition, the study examined the mineralization (TOC), photodegradation process, and photocatalytic reaction kinetics of MB and phenol.


Assuntos
Nanocompostos , Luz Solar , Grafite/química , Iluminação , Azul de Metileno/química , Nanocompostos/química , Fenol/química
5.
Int J Mol Sci ; 23(8)2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35456904

RESUMO

The presence of food contaminants can cause foodborne illnesses, posing a severe threat to human health. Therefore, a rapid, sensitive, and convenient method for monitoring food contaminants is eagerly needed. The complex matrix interferences of food samples and poor performance of existing sensing probes bring significant challenges to improving detection performances. Nanocomposites with multifunctional features provide a solution to these problems. The combination of the superior characteristics of magnetic nanoparticles (MNPs) and quantum dots (QDs) to fabricate magnetic fluorescent quantum dots (MNPs@QDs) nanocomposites are regarded as an ideal multifunctional probe for food contaminants analysis. The high-efficiency pretreatment and rapid fluorescence detection are concurrently integrated into one sensing platform using MNPs@QDs nanocomposites. In this review, the contemporary synthetic strategies to fabricate MNPs@QDs, including hetero-crystalline growth, template embedding, layer-by-layer assembly, microemulsion technique, and one-pot method, are described in detail, and their advantages and limitations are discussed. The recent advances of MNPs@QDs nanocomposites in detecting metal ions, foodborne pathogens, toxins, pesticides, antibiotics, and illegal additives are comprehensively introduced from the perspectives of modes and detection performances. The review ends with current challenges and opportunities in practical applications and prospects in food contaminants analysis, aiming to promote the enthusiasm for multifunctional sensing platform research.


Assuntos
Nanocompostos , Nanopartículas , Pontos Quânticos , Corantes , Corantes Fluorescentes/química , Análise de Alimentos , Humanos , Magnetismo , Nanocompostos/química
6.
Int J Mol Sci ; 23(8)2022 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-35457150

RESUMO

Synthetic bioactive nanocomposites show great promise in biomedicine for use in tissue growth, wound healing and the potential for bioengineered skin substitutes. Hydrogen-bonded supramolecular polymers (3A-PCL) can be combined with graphite crystals to form graphite/3A-PCL composites with tunable physical properties. When used as a bioactive substrate for cell culture, graphite/3A-PCL composites have an extremely low cytotoxic activity on normal cells and a high structural stability in a medium with red blood cells. A series of in vitro studies demonstrated that the resulting composite substrates can efficiently interact with cell surfaces to promote the adhesion, migration, and proliferation of adherent cells, as well as rapid wound healing ability at the damaged cellular surface. Importantly, placing these substrates under an indirect current electric field at only 0.1 V leads to a marked acceleration in cell growth, a significant increase in total cell numbers, and a remarkable alteration in cell morphology. These results reveal a newly created system with great potential to provide an efficient route for the development of multifunctional bioactive substrates with unique electro-responsiveness to manipulate cell growth and functions.


Assuntos
Grafite , Nanocompostos , Proliferação de Células , Condutividade Elétrica , Grafite/química , Grafite/farmacologia , Nanocompostos/química , Polímeros
7.
Sci Rep ; 12(1): 6887, 2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35477987

RESUMO

The present study aimed to assess the feasibility of developing low-cost multipurpose iron oxide/TiO2 nanocomposites (NCs) for use in combined antitumor therapies and water treatment applications. Larger size (≈ 100 nm) iron oxide nanoparticles (IONPs) formed magnetic core-TiO2 shell structures at high Fe/Ti ratios and solid dispersions of IONPs embedded in TiO2 matrices when the Fe/Ti ratio was low. When the size of the iron phase was comparable to the size of the crystallized TiO2 nanoparticles (≈ 10 nm), the obtained nanocomposites consisted of randomly mixed aggregates of TiO2 and IONPs. The best inductive heating and ROS photogeneration properties were shown by the NCs synthesized at 400 °C which contained the minimum amount of α-Fe2O3 and sufficiently crystallized anatase TiO2. Their cytocompatibility was assessed on cultured human and murine fibroblast cells and analyzed in relation to the adsorption of bovine serum albumin from the culture medium onto their surface. The tested nanocomposites showed excellent cytocompatibility to human fibroblast cells. The results also indicated that the environment (i.e. phosphate buffer or culture medium) used to disperse the nanomaterials prior to performing the viability tests can have a significant impact on their cytotoxicity.


Assuntos
Nanocompostos , Óxidos , Animais , Compostos Férricos/química , Compostos Férricos/toxicidade , Humanos , Camundongos , Nanocompostos/química , Nanocompostos/toxicidade , Titânio
8.
Molecules ; 27(8)2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35458752

RESUMO

In this study, we show how surface enhanced Raman spectroscopy (SERS) can be used to monitor the molecular behaviour of aspirin and tenofovir as a means of screening medication for quality control purposes. Gold-coated slides combined with gold/dextran nanoaggregates were used to provide signal enhancement of the drugs using SERS. Aspirin (10% w/v) and tenofovir (20% v/v) were analysed in the presence of the nanomaterials to determine trends in molecular response to changes in gold/dextran concentrations. Qualitative analysis of the functional groups showed specific trends where the peak area increased with polarizability, electron density and decreased atomic radii. Steric hinderance effects also affected the trends in peak area due to the amount of gold/dextran nanoparticles in solution. Statistical analysis provided accurate and precise linear relationships (R2 = 0.99) for the ester and adenine functional groups of aspirin and tenofovir, respectively. From the above findings, the combined use of gold nano-scaffolds and gold/dextran nanomaterials amplified the Raman signal from the drugs to allow for systematic evaluation of their molecular properties. Although more experiments to correlate the findings are still needed, this SERS approach shows great potential as a screening method in the quality control of medications.


Assuntos
Nanopartículas Metálicas , Nanocompostos , Aspirina , Dextranos , Ouro/química , Nanopartículas Metálicas/química , Análise Espectral Raman/métodos , Tenofovir
9.
Artigo em Inglês | MEDLINE | ID: mdl-35457660

RESUMO

Ciprofloxacin (CIP) in natural waters has been taken as a serious pollutant because of its hazardous biological and ecotoxicological effects. Here, a 3D nanocomposite photocatalyst g-C3N4/La-N-TiO2 (CN/La-N-TiO2) was successfully synthesized by a simple and reproducible in-situ synthetic method. The obtained composite was characterized by XRD, SEM, BET, TEM, mapping, IR, and UV-vis spectra. The photocatalytic degradation of ciprofloxacin was investigated by using CN/La-N-TiO2 nanocomposite. The main influential factors such as pH of the solution, initial CIP concentration, catalyst dosage, and coexisting ions were investigated in detail. The fastest degradation of CIP occurred at a pH of about 6.5, and CIP (5 mg/L starting concentration) was completely degraded in about 60 min after exposure to the simulated solar light. The removal rates were rarely affected by Na+ (10 mg·L-1), Ca2+ (10 mg·L-1), Mg2+ (10 mg·L-1), and urea (5 mg·L-1), but decreased in the presence of NO3- (10 mg·L-1). The findings indicate that CN/La-N-TiO2 nanocomposite is a green and promising photocatalyst for large-scale applications and would be a candidate for the removal of the emerging antibiotics present in the water environment.


Assuntos
Ciprofloxacina , Nanocompostos , Catálise , Luz , Nanocompostos/química , Titânio/química
10.
Environ Pollut ; 305: 119291, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35427680

RESUMO

The current study is the first attempt to prepare nanocomposites of Eleocharis dulcis biochar (EDB) with nano zero-valent Copper (nZVCu/EDB) and magnetite nanoparticles (MNPs/EDB) for batch and column scale sequestration of Congo Red dye (CR) from synthetic and natural water. The adsorbents were characterized with advanced analytical techniques. The impact of EDB, MNPs/EDB and nZVCu/EDB dosage (1-4 g/L), pH (4-10), initial concentration of CR (20-500 mg/L), interaction time (180 min) and material type to remove CR from water was examined at ambient temperature. The CR removal followed sequence of nZVCu/EDB > MNPs/EDB > EDB (84.9-98% > 77-95% > 69.5-93%) at dosage 2 g/L when CR concentration was increased from 20 to 500 mg/L. The MNPs/EDB and nZVCu/EDB showed 10.9% and 20.1% higher CR removal than EDB. The adsorption capacity of nZVCu/EDB, MNPs/EDB and EDB was 212, 193 and 174 mg/g, respectively. Freundlich model proved more suitable for sorption experiments while pseudo 2nd order kinetic model well explained the adsorption kinetics. Fixed bed column scale results revealed excellent retention of CR (99%) even at 500 mg/L till 2 h when packed column was filled with 3.0 g nZVCu/EDB, MNPs/EDB and EDB. These results revealed that nanocomposites with biochar can be applied efficiently for the decontamination of CR contaminated water.


Assuntos
Eleocharis , Nanocompostos , Poluentes Químicos da Água , Purificação da Água , Adsorção , Carvão Vegetal/química , Vermelho Congo , Cobre , Óxido Ferroso-Férrico , Concentração de Íons de Hidrogênio , Cinética , Água , Poluentes Químicos da Água/análise , Purificação da Água/métodos
11.
Artigo em Inglês | MEDLINE | ID: mdl-35447520

RESUMO

In this paper, we developed a facile route for the preparation of a novel bimetal oxide affinity chromatography (MOAC) material. The TiO2/ZrO2@MoS2 was constructed by the electrostatic interaction between titanium oxide/zirconia (w:w, 10:1) and molybdenum disulfide nanosheet. The nanocomposite has the large specific surface area (186.30 m2⋅g-1) and pore volume (0.37 cm3⋅g-1). Compared with single-metal probes, the combination of bimetallic oxides probe (TiO2/ZrO2) and hydrophilicity MoS2 support offered multitudinous affinity sites for phosphopeptides capturing from tryptic digests of protein samples under 50% acetonitrile-1% trifluoroacetate conditions. Singnificant feasibility of the TiO2/ZrO2@MoS2 nanomaterial for the enrichment of phosphopeptides under optimal conditions was proved via the bovine serum albumin (BSA) and the mixtures of ß-casein. The phosphopeptide expression was identified using ultra-performance liquid chromatography (uHPLC) separation and-linear ion trap mass spectrometry (MSn). With these affinity characters of TiO2/ZrO2@MoS2, it exhibited higher binding capacity (25 mg⋅g-1), better selectivity for phosphopeptides from ß-casein/BSA (1:2000) tryptic digests, high sensitivity (1 fmol⋅µL-1) towards phosphopeptides from ß-casein tryptic digests, and great reusability of 8 cycles test for capturing phosphopeptides. In addition, the TiO2/ZrO2@MoS2 with high sensitivity and selectivity was successfully applied to enriching phosphopeptides from nonfat milk and human serum samples. More importantly, the TiO2/ZrO2@MoS2 was further successfully applied to multi-phosphopeptides enrichment, 1779 serine, threonine and tyrosine phosphosites can be identified in A549 cell protein tryptic digest. Compared with commercial TiO2 from enrichening 416 phosphopeptide from A549 cell lysates, the successful locating of 44 phosphosites were overlapped.


Assuntos
Nanocompostos , Fosfopeptídeos , Células A549 , Caseínas/química , Cromatografia de Afinidade/métodos , Dissulfetos , Humanos , Molibdênio , Óxidos , Fosfopeptídeos/análise , Soroalbumina Bovina , Titânio/química , Zircônio/química
12.
Small ; 18(15): e2108034, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35419992

RESUMO

Surface oxygen vacancies (Vo ) regulation is an effective strategy to improve the electrochemical CO2  reduction reaction (CO2 RR) performance by lowering the activation energy barrier of CO2 ; however, the lack of precise control over the local atomic structures severely hinders the large-scale application of Vo -activated electrocatalyst for CO2 RR. Herein, an efficient strategy to facilitate CO2  activation is developed by introducing Vo into transition metal nanoparticles (NPs) with a steam-assisted chemical vapor deposition method. With the steam process, abundant surface Vo are introduced into the assembled Ni-Fe bimetallic NPs composite (H-NiFe/NG), which adjust surface Ni/Fe atoms to low-valent coordinatively unsaturated Ni (+1)/Fe (+2) sites, serving as electron-rich centers to adsorb and activate inert CO2  molecules. The as-prepared H-NiFe/NG composite exhibits excellent catalytic performance with a maximum Faradaic efficiency of 94% at -0.80 V (vs RHE) for CO production with remarkable stability. The density function theory calculations corroborate that the Ni atoms around surface Vo significantly lower the energy barrier for COOH* intermediate formation, which gives a low overpotential for reducing CO2  to CO, exhibiting superior CO2 RR performance. This general synthetic strategy provides a new insight to introduce surface Vo on transition metal for efficient CO2  reduction.


Assuntos
Nanocompostos , Vapor , Dióxido de Carbono/química , Catálise , Oxigênio
13.
Sci Rep ; 12(1): 6403, 2022 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-35431315

RESUMO

The biocompatible hybrid Zeolitic imidazolate framework-8 (ZIF-8)/structured silica nanocomposite can be loaded with antioxidants such as curcumin and resveratrol to offer multiple advantages of drug functionalization and structural stability. blastocystosis, an enteric parasite, has various outcomes and its treatment includes drugs which have side effects and do not result in a full cure. We aimed to design novel biocompatible nanocomposites containing natural antioxidant, resveratrol or curcumin and ZIF-8/mesoporous silica. We also assessed their anti-blastocystosis activities as bioactive novel nanocomposites. The nano-silica (MCM-41 and KIT-6) was synthesized using a hydrothermal technique and made composite with ZIF-8 using an ultrasonic technique. The antioxidants, curcumin and resveratrol, were loaded over ZIF-8/MCM-41 and ZIF-8/KIT-6 using a rotary evaporator technique to form novel nanocomposites with bioactive properties. The formulated nanocomposites were characterized. To test their biological activity, suspension of cultured blastocystosis cysts (subtype 3) were exposed to increasing concentrations of nanocomposites and the minimal lethal concentration of each nanocomposite was calculated. The bioactive nanocomposites (ZIF-8/KIT-6, ZIF-8/KIT-6/Resveratrol and ZIF-8/MCM-41/Curcumin) were formulated. Anti-blastocystosis activity of the tested nanocomposites was both dose and time dependent. ZIF-8/KIT-6/Resveratol showed the maximum percentage of growth inhibition (~ 100%) at a concentration of 500 µg/ml after 5 h of exposure. More than 90% of blastocystosis cysts' growth was significantly inhibited at all concentrations of ZIF-8/MCM-41/Curcumin, with different times of exposure, while it occurred only at the highest concentration of ZIF-8/KIT-6 (800 µg/ml). Using cheap, simple, reproducible and scalable techniques, we nano-formulated innovative bioactive nanocomposites, by incorporating the bioactive ZIF-8 (Zn2+ with imidazole), structured mesosilica and natural antioxidant compounds, curcumin or resveratrol, to generate multifunctional modalities. These eco-friendly, naturally based, safe, economical, biocompatible, and bioavailable nanocomposites are potential nanotherapeutics. The anti-blastocystosis results of these three nanocomposites indicate their potentially promising innovative and safe use as alternative Blastocystosis therapies.


Assuntos
Curcumina , Cistos , Nanocompostos , Zeolitas , Antioxidantes/farmacologia , Curcumina/farmacologia , Humanos , Nanocompostos/química , Resveratrol/farmacologia , Dióxido de Silício/química , Zeolitas/química , Zeolitas/farmacologia
14.
Carbohydr Polym ; 288: 119400, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35450652

RESUMO

TiO2-based materials have been developing rapidly as eco-friendly photocatalysts, but the inherent defects limited their application, such as rapid recombination of photogenerated electrons and wide bandgap. To obtain high-efficient TiO2/carbonaceous photocatalysts (TiO2/C), we prepared the nanocomposite by carbonizing titanium alginate coordination compound and studied their photocatalytic performance against methylene blue (MB) under simulated sunlight irradiation. The resultant nanocomposites were characterized by FT-IR, XPS, XRD, SEM-EDS, TG-DTG, UV-DRS, and N2 adsorption-desorption analysis. The carbon mainly existed in the outer layer of TiO2/C composites, contributing to the optical sensibilization. As a result, the degradation efficiency of sample TiO2/C-20 to MB could reach 97.47% within 15 min under simulated sunlight. The samples also possessed high stability, proved by the 0.72% reduction in photodegradation ratio after five cyclic tests. The present study proved the feasibility of preparing photocatalyst from titanium-alginate coordination compound and provided an extensible approach for preparing high-efficiency photocatalysts from a polysaccharide-based coordination compound.


Assuntos
Nanocompostos , Titânio , Alginatos , Catálise , Azul de Metileno , Nanocompostos/efeitos da radiação , Espectroscopia de Infravermelho com Transformada de Fourier , Titânio/efeitos da radiação
15.
Nanotechnology ; 33(29)2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35413702

RESUMO

Despite the anticancer effect of lupeol (Lup), low aqueous solubility can make its therapeutic usage difficult. However, polycaprolactone/Gelatin (PCL-GEL) nanofibers scaffold eliminates this problem. This study has been conducted to recognize PCL-GEL-Lup nanofibers effect on cancer cell lines. PCL-GEL solution was prepared at different ratios (8 wt% and 4 wt%) for achieving optimal nanofibers. PCL-GEL-Lup nanofibers were provided via electrospinning technique. The surface morphology of nanofibers was examined using FESEM. Functional groups were investigated by a Fourier Transform Infrared spectroscopy. Lupeol released from nanofibers was detected by a UV-Visible spectroscopy. The drug release profile confirmed the sustained release of about 80% achieved within 40 h. IC50of lupeol against ACHN and HSC-3 cell lines are 52.57 and 66.10µg ml-1respectively. The study results from aid an understanding of the fabrication of a scaffold with an optimum dose of bioactive lupeol in 6 wt% with bead free uniform diameter that is capable of binding the drug efficiently. The enhanced cytotoxicity activity by effective diffusion and elution to the target achieved in this study help to develop a nanofiber in the ongoing battle against cancer.


Assuntos
Nanocompostos , Nanofibras , Gelatina/química , Nanofibras/química , Triterpenos Pentacíclicos , Poliésteres/química , Espectroscopia de Infravermelho com Transformada de Fourier , Engenharia Tecidual/métodos , Tecidos Suporte/química
16.
Biomaterials ; 284: 121533, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35462304

RESUMO

Adenosine and lactate accumulated in tumor microenvironment are two major causes of immunosuppression, their concurrent downregulation holds promise in effective cancer immunotherapy, but remains challenging. Here, a sub-6 nm MnFe2O4 conjugated with dichloroacetic acid (DCA) nanoparticle is developed to modulate tumor glucose metabolism and ATP catabolism for reversing the tumor immunosuppressive microenvironment. The ultrasmall MnFe2O4-DCA nanoparticle can efficiently enter mitochondria and supply oxygen, improving the bioactivity of DCA to regulate glucose metabolism and reduce lactate production ca. 100 times higher than free DCA itself. Moreover, this design significantly downregulates CD39 and CD73 expression than DCA or MnFe2O4 alone, which consequently decreases the extracellular ATP catabolism. The concurrent regulation of glucose metabolism and ATP catabolism leads to increased immunostimulatory ATP level and decreased immunosuppressive adenosine and lactate levels in tumor microenvironment, eventually amplified dendritic cells maturation, enhanced cytotoxic T lymphocyte response, and improved cancer immunotherapy efficacy.


Assuntos
Ácido Dicloroacético , Nanocompostos , Adenosina , Trifosfato de Adenosina , Linhagem Celular Tumoral , Ácido Dicloroacético/farmacologia , Ácido Dicloroacético/uso terapêutico , Glucose/metabolismo , Imunossupressores , Imunoterapia , Ácido Láctico , Microambiente Tumoral
17.
Langmuir ; 38(18): 5900-5914, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35470668

RESUMO

A novel sorbent was synthesized based on MIL-53(Al) MOF grown over an aminoclay (AC) platform, called MIL-53(Al)@AC nanocomposite, via a green and facile hydrothermal method. The nanocomposite was characterized using FT-IR, PXRD, BET, TEM, FESEM, EDS, XPS, TGA, DLS, and zeta potential analyses. BET analysis represented the porous nature and great surface area of MIL-53(Al)@AC. The high crystalline structure for the synthesized nanocomposite was verified using the PXRD pattern. FESEM, EDS, TEM, and XPS analysis proved the successful decoration of MIL-53(Al) over the AC platform. Cephalosporin antibiotics cefixime (CFX) and cephalexin (CPX), which are often present in wastewaters, were utilized to examine the sorption capacity of the nanocomposite. The significant influential factors such as pH, temperature, sorbent amount, ionic strength, and impurity were discussed. At an initial pH of 7.0 ± 0.1, the highest sorption capacities of CFX and CPX on MIL-53(Al)@AC were 784.14 and 747.91 mg g-1 (T = 298 K, and sorbent amount = 0.1 g L-1), which were 1.43 and 1.47 times greater compared to that of MIL-53(Al), respectively. The evaluation of experimental results was implemented through the Langmuir and Freundlich isotherm equations. The isothermal data were described nobly by the Freundlich isotherm, which confirmed multilayer adsorption on heterogeneous surfaces (R2 > 0.970). A kinetic study indicated that the nanocomposite could adsorb the majority of cephalosporin antibiotics within 30 min. In addition, the experimental data were evaluated via pseudo-first-order, pseudo-second-order, and intraparticle diffusion models. The results indicated that the pseudo-second-order equation agreed more closely with the kinetic data (R2 > 0.990). Furthermore, the processes of adsorption were exothermic and spontaneous. The electrostatic attraction, hydrophobic interaction, π-π electron donor-acceptor effect, H-bond, and π-π stacking constituted the main sorption mechanisms. Finally, MIL-53(Al)@AC presented an excellent regeneration performance. Thus, the results revealed the potential application of the MIL-53(Al)@AC nanocomposite for water remediation.


Assuntos
Estruturas Metalorgânicas , Nanocompostos , Poluentes Químicos da Água , Adsorção , Alumínio , Cefalosporinas , Cinética , Nanocompostos/química , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/análise
18.
Colloids Surf B Biointerfaces ; 214: 112472, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35364455

RESUMO

Biodegradable polymers typically have inferior barrier properties compared to petroleum-based nonbiodegradable plastic. The addition of zinc oxide nanoparticles may enhance the functional properties of biodegradable packaging and extends the shelf life of packaged foods. Polybutylene adipate-co-terephthalate (PBAT) and thermoplastic starch (TPS) blended ZnO (1-5%) nanocomposite films were developed via blown extrusion for functional active meat packaging. The nanocomposite film morphology showed agglomeration of the nanoparticles, causing poor mechanical properties. Nanovoids formed at the interface between the polymer and nanoparticles, increasing permeability. Dispersion of ZnO nanofillers modified CO and C-O ester bonding in PBAT and increased hydrogen bonding with TPS. The interaction between ZnO and polymers increased the dispersion and reduced the agglomeration of nanoparticles. The highest ZnO content at 5% resulted in a stronger interaction between ZnO and TPS due to increased amorphous starch content, which improved homogeneous dispersion within the matrices, reducing nanoparticle size. The ZnO nanocomposite films reduced lipid oxidation and delayed microbial growth, resulting in a lower total viable count, lactic acid bacteria and yeast and mold in packaged pork meat. Higher ZnO concentrations from 3% showed microbial inhibitory effects. The growth of microorganisms was controlled by residual oxygen, morphology of the films and nanoparticle characteristics. The nanocomposite films effectively extended the shelf life by more than 3 days under refrigerated conditions.


Assuntos
Nanocompostos , Óxido de Zinco , Embalagem de Alimentos/métodos , Expectativa de Vida , Carne , Polímeros , Amido , Óxido de Zinco/farmacologia
19.
Biomacromolecules ; 23(5): 1981-1994, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35442640

RESUMO

The visualization of naturally derived cellulose nanofibrils (CNFs) and nanocrystals (CNCs) within nanocomposite materials is key to the development of packaging materials, tissue culture scaffolds, and emulsifying agents, among many other applications. In this work, we develop a versatile and efficient two-step approach based on triazine and azide-alkyne click-chemistry to fluorescently label nanocelluloses with a variety of commercially available dyes. We show that this method can be used to label bacterial cellulose fibrils, plant-derived CNFs, carboxymethylated CNFs, and CNCs with Cy5 and fluorescein derivatives to high degrees of labeling using minimal amounts of dye while preserving their native morphology and crystalline structure. The ability to tune the labeling density with this method allowed us to prepare optimized samples that were used to visualize nanostructural features of cellulose through super-resolution microscopy. The efficiency, cost-effectiveness, and versatility of this method make it ideal for labeling nanocelluloses and imaging them through advanced microscopy techniques for a broad range of applications.


Assuntos
Nanocompostos , Nanopartículas , Celulose/química , Microscopia de Fluorescência , Nanopartículas/química , Tecidos Suporte
20.
ACS Biomater Sci Eng ; 8(5): 1975-1986, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35452580

RESUMO

Biophysical cues are key distinguishing characteristics that influence tissue development and regeneration, and significant efforts have been made to alter the cellular behavior by means of cell-substrate interactions and external stimuli. Electrically conductive nanofibers are capable of treating bone defects since they closely mimic the fibrillar architecture of the bone matrix and deliver the endogenous and exogenous electric fields required to direct cell activities. Nevertheless, previous studies on conductive polymer-based scaffolds have been limited to polypyrrole, polyaniline, and poly(3,4-ethylenedioxythiophene) (PEDOT). In the present study, chemically synthesized polythiophene nanoparticles (PTh NPs) are incorporated into polycaprolactone (PCL) nanofibers, and subsequent changes in physicochemical, mechanical, and electrical properties are observed in a concentration-dependent manner. In murine preosteoblasts (MC3T3-E1), we examine how substrate properties modified by adding PTh NPs contribute to changes in the cellular behavior, including viability, proliferation, differentiation, and mineralization. Additionally, we determine that external electrical stimulation (ES) mediated by PTh NPs positively affects such osteogenic responses. Together, our results provide insights into polythiophene's potential as an electroconductive composite scaffold material.


Assuntos
Nanocompostos , Osteogênese , Animais , Proliferação de Células , Estimulação Elétrica , Camundongos , Polímeros , Pirróis , Tiofenos , Tecidos Suporte/química
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