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1.
Luminescence ; 39(8): e4850, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39129387

RESUMO

Silver vanadate nanorods were synthesized for the first time via co-precipitation, followed by ambient drying. X-ray diffraction (XRD), energy dispersive X-ray (EDX), and scanning electron microscope (SEM) analyses were utilized to investigate the structure and morphology of the nanorods. The results of these analyses confirmed the fabrication of silver vanadate nanorods. Then, to check the ability of these nanostructures to be used in the smart window, their optical properties, including the visible-ultraviolet absorption spectrum and photoluminescence (PL), were studied. The results showed that this nanostructure has maximum absorption and emission at wavelengths of 530 and 670 nm, respectively. Next, the new smart window was made with a layer of silver vanadate nanorods, and wheat, barley, millet, and beet were placed under this smart window to perform phytochemical tests. It was observed that silver vanadate nanorods could shift the green wavelength to higher wavelengths and efficiently improve the phytochemical properties of the mentioned plants.


Assuntos
Nanotubos , Prata , Vanadatos , Nanotubos/química , Vanadatos/química , Prata/química , Luz Solar , Luminescência , Compostos Fitoquímicos/química , Triticum/química , Beta vulgaris/química , Compostos de Prata/química
2.
J Inorg Biochem ; 260: 112687, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39142056

RESUMO

The interactions of polyoxovanadates (POVs) with proteins have increasingly attracted interest in recent years due to their potential biomedical applications. This is especially the case because of their redox and catalytic properties, which make them interesting for developing artificial metalloenzymes. Organic-inorganic hybrid hexavanadates in particular offer several advantages over all-inorganic POVs. However, they have been scarcely investigated in biological systems even though, as shown in this work, hybrid hexavanadates are highly stable in aqueous solutions up to relatively high pH. Therefore, a novel bis-biotinylated hexavanadate was synthesized and shown to selectively interact with two biotin-binding proteins, avidin and streptavidin. Bridging interactions between multiple proteins led to their self-assembly into supramolecular bio-inorganic hybrid systems that have potential as artificial enzymes with the hexavanadate core as a redox-active cofactor. Moreover, the structure and charge of the hexavanadate core were determined to enhance the binding affinity and slightly alter the secondary structure of the proteins, which affected the size and speed of formation of the assemblies. Hence, tuning the polyoxometalate (POM) core of hybrid POMs (HPOMs) with protein-binding ligands has been demonstrated to be a potential strategy for controlling the self-assembly process while also enabling the formation of novel POM-based biomaterials that could be of interest in biomedicine.


Assuntos
Oxirredução , Vanadatos , Vanadatos/química , Estreptavidina/química , Avidina/química , Compostos de Tungstênio/química
3.
Bioelectrochemistry ; 160: 108773, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38972159

RESUMO

A biofunctional immunosensor combining photoelectrochemical (PEC) and electrochemical (EC) was proposed for the quantitative detection of the liver cancer marker alpha-fetoprotein (AFP) in human blood. BiVO4/BiOI-MWCNTs photoactive materials were first prepared on conductive glass FTO, and the photoelectrode was functionalized by chitosan and glutaraldehyde. Then, the AFP capture antibody (Ab1) was successfully modified on the photoelectrode, and the label-free rapid detection of AFP antigen was achieved by PEC. In addition, Au@PdPt nanospheres were also used as a marker for binding to AFP detection antibody (Ab2). Due to the excellent catalytic properties of Au@PdPt in EC reaction, a signal increase in the EC response can be achieved when Ab2 binds to the AFP antigen, which ensures high sensitivity for the detection of AFP. The detection limits of PEC and EC are 0.050 pg/mL and 0.014 pg/mL, respectively. The sensor also possesses good specificity, stability and reproducibility, shows excellent performance in the detection of clinical samples and has good clinical applicability.


Assuntos
Técnicas Biossensoriais , Bismuto , Técnicas Eletroquímicas , Ouro , Vanadatos , alfa-Fetoproteínas , alfa-Fetoproteínas/análise , alfa-Fetoproteínas/imunologia , Ouro/química , Humanos , Bismuto/química , Vanadatos/química , Técnicas Eletroquímicas/métodos , Técnicas Biossensoriais/métodos , Imunoensaio/métodos , Nanotubos de Carbono/química , Paládio/química , Limite de Detecção , Platina/química , Nanopartículas Metálicas/química , Anticorpos Imobilizados/química , Anticorpos Imobilizados/imunologia
4.
Chemosphere ; 363: 142746, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38969223

RESUMO

Vanadate-based photocatalysts have recently attracted substantial attention owing to their outstanding photocatalytic activity for degrading organic pollutants and generating energy via photocatalytic processes. However, the relatively high price of vanadium has hindered the development of vanadate-based photocatalysts for various applications. Spent catalysts obtained from oil refineries typically contain a significant quantity of vanadium, making them valuable for recovery and utilization as precursors for the production of high-value-added photocatalysts. In this study, we transformed the V present in spent catalysts produced by the petrochemical industry into ternary vanadate-based photocatalysts [BiVO4/InVO4/Ag3VO4 (BVO/IVO/AVO, respectively)] designed for water remediation. The ternary composites revealed an enhanced photocatalytic capability, which was 1.42 and 5.1 times higher than those of the binary BVO/IVO and pristine AVO due to the facilitated charge separation. The ternary photocatalysts not only effectively treated wastewater containing various organic dyes, such as methylene blue (MB), rhodamine 6G (R6G), and brilliant green (BG), but also exhibited remarkable photocatalytic performance in the degradation of antibiotics, reduction of Cr(VI), and bacterial inactivation. This paper proposes a feasible route for recycling industrial waste as a source of vanadium to produce highly efficient vanadate-based photocatalysts.


Assuntos
Bismuto , Vanadatos , Vanádio , Poluentes Químicos da Água , Purificação da Água , Catálise , Vanadatos/química , Poluentes Químicos da Água/química , Vanádio/química , Purificação da Água/métodos , Bismuto/química , Corantes/química , Águas Residuárias/química , Processos Fotoquímicos
5.
J Inorg Biochem ; 260: 112672, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39079338

RESUMO

Melanoma is a skin cancer that arises from melanocytes and can spread quickly to the other organs of the body, if not treated early. Generally, melanoma shows an inherent resistance to conventional therapies. In this regard, new potential drugs are being developed as possible treatments for melanoma. In this paper, we report the synthesis of a new decavanadate compound with organic molecules for a potential therapeutic application. The tetra-[methylimidazolium] dihydrogen decavanadate(V) salt (C4H7N2)4[H2V10O28] is characterized by single-crystal X-ray diffraction, by FT-IR, UV-Vis and 51V NMR spectroscopy, as well as by thermal analysis (TGA and DSC). The compound crystallizes in the monoclinic centrosymmetric space group P21/c. Its formula unit consists of one dihydrogen decavanadate anion [H2V10O28]4- and four organic 4-methylimidazolium cations (C4H7N2)+. Important intermolecular interactions are N-H···O and O-H···O hydrogen bonds and π-π stacking interactions between the organic cations, revealed by analysis of the Hirshfeld surface and its two-dimensional fingerprint plots. Interestingly, this compound inhibits the viability of IGR39 cells with IC50 values of 14.65 µM and 4 µM after 24 h and 72 h of treatment, respectively. The analysis of its effect by flow cytometry using an Annexin V-FITC/IP cell labeling, showed that (C4H7N2)4H2V10O28 compound induced IGR39 cell apoptosis and necrosis. Molecular docking studies performed against TNFR1 and GPR40, as putative targets, suggest that the (C4H7N2)4[H2V10O28] compound may act as inhibitor of these proteins, known to be overexpressed in melanoma cells. Therefore, we could consider it as a new potential metallodrug against melanoma.


Assuntos
Antineoplásicos , Imidazóis , Melanoma , Vanadatos , Humanos , Vanadatos/química , Vanadatos/farmacologia , Vanadatos/síntese química , Melanoma/tratamento farmacológico , Melanoma/patologia , Melanoma/metabolismo , Linhagem Celular Tumoral , Imidazóis/química , Imidazóis/farmacologia , Imidazóis/síntese química , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos
6.
Food Chem ; 459: 140353, 2024 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-39024884

RESUMO

This study presents a facial and quick electrochemical sensor platform that offers remarkable water and food safety applications. The present work represents a study of the synthesis and characterization for efficient cerium vanadate (CeVO4) with a functionalized carbon nanofiber (f-CNF) decorated electrode, which is a highly effective electrode modifier for sensitive nitrite detection. The CeVO4 nanoparticles were synthesized using the facial hydrothermal technique, and a composite (CeVO4@f-CNF) was prepared using the sonication method. Afterward, the produced materials were confirmed with spectroscopic and microscopic analysis. The electrochemical behavior of nitrite was studied through cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The DPV analysis depicts an excellent linear range of 0.1-1033 µM and a promising detection limit of 0.004 µM for the proposed electrode. The CeVO4@f-CNF electrode was applied to detect nitrite in water and meat samples. The proposed electrochemical sensor attributes the significant results towards the detection of nitrite.


Assuntos
Carbono , Cério , Técnicas Eletroquímicas , Eletrodos , Limite de Detecção , Nanofibras , Nitritos , Vanadatos , Nitritos/análise , Nitritos/química , Vanadatos/química , Cério/química , Nanofibras/química , Carbono/química , Carne/análise , Animais , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise
7.
Angew Chem Int Ed Engl ; 63(31): e202406669, 2024 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-38842919

RESUMO

The high-resolution X-ray structures of the model protein lysozyme in the presence of the potential drug [VIVO(acetylacetonato)2] from crystals grown in 1.1 M NaCl, 0.1 M sodium acetate at pH 4.0 reveal the binding to the protein of different and unexpected mixed-valence cage-like polyoxidovanadates (POVs): [V15O36(OH2)]5-, which non-covalently interacts with the lysozyme surface, [V15O33(OH2)]+ and [V20O51(OH2)]n- (this latter based on an unusual {V18O43} cage) which covalently bind the protein. EPR spectroscopy confirms the partial oxidation of VIV to VV and the formation of mixed-valence species. The results indicate that the interaction with proteins can stabilize the structure of unexpected - both for dimension and architecture - POVs, not observed in aqueous solution.


Assuntos
Muramidase , Vanadatos , Muramidase/química , Muramidase/metabolismo , Vanadatos/química , Modelos Moleculares , Cristalografia por Raios X
8.
J Inorg Biochem ; 258: 112619, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38823066

RESUMO

The present study describes a novel antimicrobial mechanism based on Sodium Orthovanadate (SOV), an alkaline phosphatase inhibitor. Scanning electron microscopy (SEM), transmission electron microscopy (TEM) and atomic force microscopy (AFM) were employed to examine the surface morphologies of the test organism, Escherichia coli (E. coli), during various antibacterial phases. Our results indicated that SOV kills bacteria by attacking cell wall growth and development, leaving E. coli's outer membrane intact. Our antimicrobial test indicated that the MIC of SOV for both E. coli and Lactococcus lactis (L. lactis) is 40 µM. A combination of quantum mechanical calculations and vibrational spectroscopy revealed that divanadate from SOV strongly coordinates with Ca2+ and Mg2+, which are the activity centers for the phosphatase that regulates bacterial cell wall synthesis. The current study is the first to propose the antibacterial mechanism caused by SOV attacking cell wall.


Assuntos
Antibacterianos , Escherichia coli , Vanadatos , Vanadatos/química , Vanadatos/farmacologia , Escherichia coli/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Lactococcus lactis , Testes de Sensibilidade Microbiana , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Parede Celular/efeitos dos fármacos , Fosfatase Alcalina/metabolismo , Fosfatase Alcalina/antagonistas & inibidores
9.
J Colloid Interface Sci ; 674: 29-38, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38909592

RESUMO

Persistent inflammation and bacterial infection commonly occur during the wound healing process, necessitating urgent development of effective strategies for treating drug-resistant bacterial infections. In this study, bismuth vanadate (BiVO4) was successfully synthesized as an antibacterial agent that promotes wound healing. Through In vitro antibacterial experiments, it was observed that the prepared BiVO4 exhibited excellent performance in catalyzing H2O2 to produce hydroxyl radicals (OH) at a lower concentration (0.2 mg mL-1), resulting in significant antibacterial effects against Gram-negative Extended-Spectrum ß-Lactamases-Producing Escherichia coli (ESBL-E. coli) strains. Furthermore, biosafety tests, cell scratch experiments, and ESBL-E. coli infected wound rat model experiments demonstrated high biocompatibility of BiVO4 with a cell survival rate exceeding 85 %. Additionally, BiVO4 promoted the production of vascular endothelial growth factors and fibroblasts migration while contributing to collagen production, effectively facilitating immune reconstruction at the wound site. By integrating peroxidase (POD)-like under acidic conditions (pH 4) and catalase (CAT)-like catalytic activities at under neutral conditions (pH 7), BiVO4 exhibited the ability to activate free radical sterilization and accelerate wound healing by activating O2. Therefore, our findings provide evidence for a dual enzyme regulatory mechanism involving antibacterial properties and promotion of wound tissue reconstruction for potential application in both antibacterial treatment and wound healing.


Assuntos
Antibacterianos , Bismuto , Escherichia coli , Vanadatos , Cicatrização , Vanadatos/química , Vanadatos/farmacologia , Bismuto/química , Bismuto/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Concentração de Íons de Hidrogênio , Antibacterianos/farmacologia , Antibacterianos/química , Ratos , Catálise , Escherichia coli/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Peróxido de Hidrogênio/metabolismo , Testes de Sensibilidade Microbiana , Humanos , Sobrevivência Celular/efeitos dos fármacos , Ratos Sprague-Dawley , Tamanho da Partícula , Propriedades de Superfície
10.
Nature ; 630(8016): 509-515, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38750366

RESUMO

Temperature profoundly affects macromolecular function, particularly in proteins with temperature sensitivity1,2. However, its impact is often overlooked in biophysical studies that are typically performed at non-physiological temperatures, potentially leading to inaccurate mechanistic and pharmacological insights. Here we demonstrate temperature-dependent changes in the structure and function of TRPM4, a temperature-sensitive Ca2+-activated ion channel3-7. By studying TRPM4 prepared at physiological temperature using single-particle cryo-electron microscopy, we identified a 'warm' conformation that is distinct from those observed at lower temperatures. This conformation is driven by a temperature-dependent Ca2+-binding site in the intracellular domain, and is essential for TRPM4 function in physiological contexts. We demonstrated that ligands, exemplified by decavanadate (a positive modulator)8 and ATP (an inhibitor)9, bind to different locations of TRPM4 at physiological temperatures than at lower temperatures10,11, and that these sites have bona fide functional relevance. We elucidated the TRPM4 gating mechanism by capturing structural snapshots of its different functional states at physiological temperatures, revealing the channel opening that is not observed at lower temperatures. Our study provides an example of temperature-dependent ligand recognition and modulation of an ion channel, underscoring the importance of studying macromolecules at physiological temperatures. It also provides a potential molecular framework for deciphering how thermosensitive TRPM channels perceive temperature changes.


Assuntos
Ativação do Canal Iônico , Canais de Cátion TRPM , Temperatura , Humanos , Trifosfato de Adenosina/metabolismo , Trifosfato de Adenosina/farmacologia , Sítios de Ligação , Cálcio/metabolismo , Microscopia Crioeletrônica , Células HEK293 , Ativação do Canal Iônico/efeitos dos fármacos , Ligantes , Modelos Moleculares , Ligação Proteica , Domínios Proteicos , Especificidade por Substrato , Canais de Cátion TRPM/agonistas , Canais de Cátion TRPM/antagonistas & inibidores , Canais de Cátion TRPM/química , Canais de Cátion TRPM/metabolismo , Vanadatos/química , Vanadatos/farmacologia , Vanadatos/metabolismo
11.
Water Res ; 257: 121747, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38733964

RESUMO

Contamination of aquifers by a combination of vanadate [V(V)] and nitrate (NO3-) is widespread nowadays. Although bioremediation of V(V)- and nitrate-contaminated environments is possible, only a limited number of functional species have been identified to date. The present study demonstrates the effectiveness of V(V) reduction and denitrification by a denitrifying bacterium Acidovorax sp. strain BoFeN1. The V(V) removal efficiency was 76.5 ± 5.41 % during 120 h incubation, with complete removal of NO3- within 48 h. Inhibitor experiments confirmed the involvement of electron transport substances and denitrifying enzymes in the bioreduction of V(V) and NO3-. Cyt c and riboflavin were important for extracellular V(V) reduction, with quinone and EPS more significant for NO3- removal. Intracellular reductive compounds including glutathione and NADH directly reduce V(V) and NO3-. Reverse transcription quantitative PCR confirmed the important roles of nirK and napA genes in regulating V(V) reduction and denitrification. Bioaugmentation by strain BoFeN1 increased V(V) and NO3- removal efficiency by 55.3 % ± 2.78 % and 42.1 % ± 1.04 % for samples from a contaminated aquifer. This study proposes new microbial resources for the bioremediation of V(V) and NO3-contaminated aquifers, and contributes to our understanding of coupled vanadium, nitrogen, and carbon biogeochemical processes.


Assuntos
Biodegradação Ambiental , Comamonadaceae , Desnitrificação , Nitratos , Oxirredução , Vanadatos , Comamonadaceae/metabolismo , Comamonadaceae/genética , Vanadatos/metabolismo , Nitratos/metabolismo , Poluentes Químicos da Água/metabolismo , Água Subterrânea/microbiologia
12.
Environ Sci Technol ; 58(21): 9456-9465, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38745405

RESUMO

The elimination of uranium from radioactive wastewater is crucial for the safe management and operation of environmental remediation. Here, we present a layered vanadate with high acid/base stability, [Me2NH2]V3O7, as an excellent ion exchanger capturing uranyl from highly complex aqueous solutions. The material possesses an indirect band gap, ferromagnetic characteristic and a flower-like morphology comprising parallel nanosheets. The layered structure of [Me2NH2]V3O7 is predominantly upheld by the H-bond interaction between anionic framework [V3O7]nn- and intercalated [Me2NH2]+. The [Me2NH2]+ within [Me2NH2]V3O7 can be readily exchanged with UO22+. [Me2NH2]V3O7 exhibits high exchange capacity (qm = 176.19 mg/g), fast kinetics (within 15 min), high removal efficiencies (>99%), and good selectivity against an excess of interfering ions. It also displays activity for UO22+ ion exchange over a wide pH range (2.00-7.12). More importantly, [Me2NH2]V3O7 has the capability to effectively remove low-concentration uranium, yielding a residual U concentration of 13 ppb, which falls below the EPA-defined acceptable limit of 30 ppb in typical drinking water. [Me2NH2]V3O7 can also efficiently separate UO22+ from Cs+ or Sr2+ achieving the highest separation factors (SFU/Cs of 589 and SFU/Sr of 227) to date. The BOMD and DFT calculations reveal that the driving force of ion exchange is dominated by the interaction between UO22+ and [V3O7]nn-, whereas the ion exchange rate is influenced by the mobility of UO22+ and [Me2NH2]+. Our experimental findings indicate that [Me2NH2]V3O7 can be considered as a promising uranium scavenger for environmental remediation. Additionally, the simulation results provide valuable mechanistic interpretations for ion exchange and serve as a reference for designing novel ion exchangers.


Assuntos
Urânio , Vanadatos , Urânio/química , Vanadatos/química , Troca Iônica , Poluentes Radioativos da Água/química , Cinética
13.
Environ Toxicol Pharmacol ; 108: 104465, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38734396

RESUMO

Malaria represents the greatest global health burden among all parasitic diseases, with drug resistance representing the primary obstacle to control efforts. Sodium metavanadate (NaVO3) exhibits antimalarial activity against the Plasmodium yoelii yoelii (Pyy), yet its precise antimalarial mechanism remains elusive. This study aimed to assess the antimalarial potential of NaVO3, evaluate its genotoxicity, and determine the production of reactive oxygen and nitrogen species (ROS/RNS) in Pyy. CD-1 mice were infected and divided into two groups: one treated orally with NaVO3 (10 mg/kg/day for 4 days) and the other untreated. A 50% decrease in parasitemia was observed in treated mice. All experimental days demonstrated DNA damage in exposed parasites, along with an increase in ROS and RNS on the fifth day, suggesting a possible parasitostatic effect. The results indicate that DNA is a target of NaVO3, but further studies are necessary to fully elucidate the mechanisms underlying its antimalarial activity.


Assuntos
Antimaláricos , Dano ao DNA , Plasmodium yoelii , Espécies Reativas de Nitrogênio , Espécies Reativas de Oxigênio , Vanadatos , Animais , Plasmodium yoelii/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Antimaláricos/toxicidade , Antimaláricos/farmacologia , Espécies Reativas de Nitrogênio/metabolismo , Vanadatos/toxicidade , Vanadatos/farmacologia , Malária/tratamento farmacológico , Masculino , Parasitemia , Feminino
14.
J Inorg Biochem ; 257: 112610, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38761580

RESUMO

Drug resistance has been a major problem for cancer chemotherapy, especially for glioblastoma multiforme that is aggressive, heterogeneous and recurrent with <3% of a five-year survival and limited methods of clinical treatment. To overcome the problem, great efforts have recently been put in searching for agents inducing death of tumor cells via various non-apoptotic pathways. In the present work, we report for the first time that vanadyl complexes, i.e. bis(acetylacetonato)oxidovanadium (IV) (VO(acac)2), can cause mitotic catastrophe and methuotic death featured by catastrophic macropinocytic vacuole accumulation particularly in glioblastoma cells (GCs). Hence, VO(acac)2 strongly suppressed growth of GCs with both in vitro (IC50 = 4-6 µM) and in vivo models, and is much more potent than the current standard-of-care drug Temozolomide. The selective index is as high as ∼10 or more on GCs over normal neural cells. Importantly, GCs respond well to vanadium treatment regardless whether they are carrying IDH1 wild type gene that causes drug resistance. VO(acac)2 may induce methuosis via the Rac-Mitogen-activated protein kinase kinase 4 (MKK4)-c-Jun N-terminal kinase (JNK) signaling pathway. Furthermore, VO(acac)2-induced methuosis is not through a immunogenicity mechanism, making vanadyl complexes safe for interventional therapy. Overall, our results may encourage development of novel vanadium complexes promising for treatment of neural malignant tumor cells.


Assuntos
Complexos de Coordenação , Glioblastoma , Mitose , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Glioblastoma/metabolismo , Humanos , Mitose/efeitos dos fármacos , Animais , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Antineoplásicos/química , Camundongos , Vanadatos/farmacologia , Vanadatos/química , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/metabolismo , Camundongos Nus
15.
Future Microbiol ; 19(8): 655-665, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38700286

RESUMO

Aim: To evaluate the biological and mechanical properties of an adhesive with nanostructured silver vanadate (AgVO3). Materials & methods: Specimens in poly(methyl methacrylate) (PMMA) were treated with Ultra Corega Cream (UCCA) denture adhesive with or without AgVO3. Biofilms of Candida albicans, Candida glabrata and Streptococcus mutans were grown and the viable cells counted. Fluorescence microscopy was used. The viability of the VERO cell and adhesive strength were evaluated. Results: All concentrations of AgVO3 reduced the biofilm formation and showed no cytotoxic effect. At 5 min and 24 h, UCCA with 5 and 10% AgVO3 showed better performance, respectively. Conclusion: AgVO3 promoted the antibiofilm activity of the adhesive, with a positive effect on the adhesive strength, and was biocompatible.


What is this summary about? Some people wear false teeth called dentures. They use a special glue to keep these false teeth in their mouths. It is important to clean dentures well and remove the glue every day. If the dentures get dirty, they can cause infections of the gums. Doctors and dentists can help, but sometimes medicines do not work well. This study checked to see whether adding a medicine that can kill bacteria into the glue could stop gum swelling and other illnesses, or make them better.What were the results? The glue containing the medicine killed microbes like fungi and bacteria. It also stuck things together well and was safe to use.What do the results mean? Using this special glue could help people with dentures to avoid illness.


Assuntos
Biofilmes , Streptococcus mutans , Vanadatos , Biofilmes/efeitos dos fármacos , Vanadatos/farmacologia , Animais , Células Vero , Chlorocebus aethiops , Streptococcus mutans/efeitos dos fármacos , Materiais Biocompatíveis/farmacologia , Candida albicans/efeitos dos fármacos , Candida albicans/fisiologia , Prata/farmacologia , Prata/química , Dentaduras/microbiologia , Teste de Materiais , Polimetil Metacrilato/química , Cimentos Dentários/farmacologia , Cimentos Dentários/química , Aderência Bacteriana/efeitos dos fármacos , Adesivos/farmacologia , Adesivos/química
16.
Biotechnol Bioeng ; 121(9): 2780-2792, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38711263

RESUMO

Pretreatment is crucial for effective enzymatic saccharification of lignocellulose such as sugarcane bagasse (SCB). In the present study, SCB was pretreated with five kinds of heterogeneous Fenton-like systems (HFSs), respectively, in which α-FeOOH, α-Fe2O3, Fe3O4, and FeS2 worked as four traditional heterogeneous Fenton-like catalysts (HFCs), while FeVO4 worked as a novel HFC. The enzymatic reducing sugar conversion rate was then compared among SCB after different heterogeneous Fenton-like pretreatments (HFPs), and the optimal HFS and pretreatment conditions were determined. The mechanism underlying the difference in saccharification efficiency was elucidated by analyzing the composition and morphology of SCB. Moreover, the ion dissolution characteristics, variation of pH and Eh values, H2O2 and hydroxyl radical (·OH) concentration of FeVO4 and α-Fe2O3 HFSs were compared. The results revealed that the sugar conversion rate of SCB pretreated with FeVO4 HFS reached up to 58.25%, which was obviously higher than that under other HFPs. In addition, the surface morphology and composition of the pretreated SCB with FeVO4 HFS were more conducive to enzymatic saccharification. Compared with α-Fe2O3, FeVO4 could utilize H2O2 more efficiently, since the dissolved Fe3+ and V5+ can both react with H2O2 to produce more ·OH, resulting in a higher hemicellulose and lignin removal rate and a higher enzymatic sugar conversion rate. It can be concluded that FeVO4 HFP is a promising approach for lignocellulose pretreatment.


Assuntos
Celulose , Peróxido de Hidrogênio , Ferro , Saccharum , Vanadatos , Saccharum/química , Saccharum/metabolismo , Celulose/química , Celulose/metabolismo , Peróxido de Hidrogênio/metabolismo , Peróxido de Hidrogênio/química , Ferro/química , Ferro/metabolismo , Vanadatos/química , Celulase/química , Celulase/metabolismo , Lignina/química , Lignina/metabolismo
17.
ChemSusChem ; 17(17): e202400027, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-38588020

RESUMO

An in-depth investigation was conducted on a promising composite material (BiVO4/TiO2), focusing on its potential toxicity, photoinduced catalytic properties, as well as its antibiofilm and antimicrobial functionalities. The preparation process involved the synthesis of 2D TiO2 using the lyophilization method, which was subsequently functionalized with sphere-like BiVO4 through wet impregnation. Finally, we developed BiVO4/TiO2 S-scheme heterojunctions which can greatly promote the separation of electron-hole pairs to achieve high photocatalytic performance. The evaluation of concentration- and time-dependent viability inhibition was performed on human lung carcinoma epithelial A549 cells. This assessment included the estimation of glutathione levels and mitochondrial dehydrogenase activity. Significantly, the BiVO4/TiO2 composite demonstrated minimal toxicity towards A549 cells. Impressively, the BiVO4/TiO2 composite exhibited notable photocatalytic performance in the degradation of rhodamine B (k=0.135 min-1) and phenol (k=0.016 min-1). In terms of photoinduced antimicrobial performance, the composite effectively inactivated both gram-negative E. coli and gram-positive E. faecalis bacteria upon 60 minutes of UV-A light exposure, resulting in a significant log 6 (log 10 CFU/mL) reduction in bacterial count. In addition, a 49 % reduction of E. faecalis biofilm was observed. These promising results can be attributed to the unique 2D morphology of TiO2 modified by sphere-like BiVO4, leading to an increased generation of (intracellular) hydroxyl radicals, which plays a crucial role in the treatments of both organic pollutants and bacteria. This research has significant potential for various applications, particularly in addressing environmental contamination and microbial infections.


Assuntos
Antibacterianos , Bismuto , Escherichia coli , Processos Fotoquímicos , Titânio , Vanadatos , Titânio/química , Bismuto/química , Vanadatos/química , Vanadatos/farmacologia , Humanos , Catálise , Antibacterianos/química , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Células A549 , Enterococcus faecalis/efeitos dos fármacos , Nanoestruturas/química , Rodaminas/química , Fotólise , Sobrevivência Celular/efeitos dos fármacos , Biofilmes/efeitos dos fármacos
18.
J Dent ; 145: 104984, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38583645

RESUMO

OBJECTIVES: To incorporate the nanostructured silver vanadate decorated with silver nanoparticles (AgVO3) into denture base materials: heat-cured (HC) and 3D printed (3DP) resins, at concentrations of 2.5 %, 5 %, and 10 %; and to evaluate the antimicrobial activity in two multi-species biofilm: (1) Candida albicans, Candida glabrata, and Streptococcus mutans, (2) Candida albicans, Pseudomonas aeruginosa, and Staphylococcus aureus, and the wettability. METHODS: The AgVO3 was added to the HC powder, and printed samples were coated with 3DP with AgVO3 incorporated. After biofilm formation, the antimicrobial activity was evaluated by colony forming units per milliliter (CFU/mL), metabolic activity, and epifluorescence microscopy. Wettability was assessed by the contact angles with water and artificial saliva. RESULTS: In biofilm (1), HC-5 % and HC-10 % showed activity against S. mutans, HC-10 % against C. glabrata, and HC-10 % and 3DP-10 % had higher CFU/mL of C. albicans. 3DP-5 % had lower metabolic activity than the 3DP control. In biofilm (2), HC-10 % reduced S. aureus and P. aeruginosa, and HC-5 %, 3DP-2.5 %, and 3DP-5 % reduced S. aureus. 3DP incorporated with AgVO3, HC-5 %, and HC-10 % reduced biofilm (2) metabolic activity. 3DP-5 % and 3DP-10 % increased wettability with water and saliva. CONCLUSION: HC-10 % was effective against C. glabrata, S. mutans, P. aeruginosa, and S. aureus, and HC-5 % reduced S. mutans and S. aureus. For 3DP, 2.5 % and 5 % reduced S. aureus. The incorporation of AgVO3 into both resins reduced the metabolic activity of biofilms but had no effect on C. albicans. The wettability of the 3DP with water and saliva increased with the addition of AgVO3. CLINICAL SIGNIFICANCE: The incorporation of silver vanadate into the denture base materials provides antimicrobial efficacy and can prevent the aggravation of oral and systemic diseases. The incorporation of nanomaterials into printed resins is challenging and the coating is an alternative to obtain the inner denture base with antimicrobial effect.


Assuntos
Biofilmes , Candida albicans , Bases de Dentadura , Nanopartículas Metálicas , Pseudomonas aeruginosa , Prata , Staphylococcus aureus , Streptococcus mutans , Vanadatos , Molhabilidade , Biofilmes/efeitos dos fármacos , Streptococcus mutans/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Vanadatos/farmacologia , Vanadatos/química , Pseudomonas aeruginosa/efeitos dos fármacos , Prata/farmacologia , Prata/química , Bases de Dentadura/microbiologia , Nanopartículas Metálicas/química , Anti-Infecciosos/farmacologia , Candida glabrata/efeitos dos fármacos , Impressão Tridimensional , Teste de Materiais , Humanos , Nanoestruturas , Compostos de Prata/farmacologia , Compostos de Prata/química , Materiais Dentários/química , Materiais Dentários/farmacologia
20.
Langmuir ; 40(17): 9155-9169, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38641555

RESUMO

A lack of eco-friendly, highly active photocatalyst for peroxymonosulfate (PMS) activation and unclear environmental risks are significant challenges. Herein, we developed a double S-scheme Fe2O3/BiVO4(110)/BiVO4(010)/Fe2O3 photocatalyst to activate PMS and investigated its impact on wheat seed germination. We observed an improvement in charge separation by depositing Fe2O3 on the (010) and (110) surfaces of BiVO4. This enhancement is attributed to the formation of a dual S-scheme charge transfer mechanism at the interfaces of Fe2O3/BiVO4(110) and BiVO4(010)/Fe2O3. By introducing PMS into the system, photogenerated electrons effectively activate PMS, generating reactive oxygen species (ROS) such as hydroxyl radicals (·OH) and sulfate radicals (SO4·-). Among the tested systems, the 20% Fe2O3/BiVO4/Vis/PMS system exhibits the highest catalytic efficiency for norfloxacin (NOR) removal, reaching 95% in 40 min. This is twice the catalytic efficiency of the Fe2O3/BiVO4/PMS system, 1.8 times that of the Fe2O3/BiVO4 system, and 5 times that of the BiVO4 system. Seed germination experiments revealed that Fe2O3/BiVO4 heterojunction was beneficial for wheat seed germination, while PMS had a significant negative effect. This study provides valuable insights into the development of efficient and sustainable photocatalytic systems for the removal of organic pollutants from wastewater.


Assuntos
Bismuto , Compostos Férricos , Luz , Norfloxacino , Peróxidos , Vanadatos , Vanadatos/química , Vanadatos/efeitos da radiação , Bismuto/química , Norfloxacino/química , Norfloxacino/efeitos da radiação , Catálise/efeitos da radiação , Compostos Férricos/química , Peróxidos/química , Processos Fotoquímicos , Triticum/química , Triticum/efeitos da radiação
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