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1.
Bull Exp Biol Med ; 176(4): 501-504, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38491259

RESUMO

High X-ray absorption combined with photothermal properties make bismuth nanoparticles (Bi NP) a promising agent for multimodal cancer theranostics. However, the synthesis of Bi NP by the "classical" chemical methods has numerous limitations, including potential toxicity of the produced nanomaterials. Here we studied in vitro toxicity of laser-synthesized Bi NP coated with Pluronic F-127 on mouse fibroblast cell line L929. The survival of L929 cells decreased linearly with increasing the concentration of Bi NP in a concentration range of 3-500 µg/ml; the LC50 value was 57 µg/ml. The unique combination of functional properties and moderate toxicity of the laser-synthesized Bi NP makes them a new promising platform for sensitization of multimodal cancer theranostics.


Assuntos
Nanopartículas Metálicas , Animais , Camundongos , Bismuto/toxicidade , Bismuto/química , Linhagem Celular Tumoral , Nanopartículas Metálicas/toxicidade , Nanopartículas Metálicas/química , Nanopartículas/toxicidade , Nanopartículas/química , Nanoestruturas , Neoplasias/metabolismo , Fototerapia/métodos
2.
Langmuir ; 40(13): 7060-7066, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38513212

RESUMO

Nanosheet arrays with stable signal output have become promising photoactive materials for photoelectrochemical (PEC) immunosensors. However, an essential concern is the facile recombination of carriers in one-component nanoarrays, which cannot be readily prevented, ultimately resulting in weak photocurrent signals. In this study, an immunosensor using gold nanoparticle-anchored BiOI/Bi2S3 nanosheet arrays (BiOI/Bi2S3/Au) as a signal converter was fabricated for sensitive detection of cardiac troponin I (cTnI). The ternary nanosheet arrays were prepared by a simple method in which Bi2S3 was well-coated on the BiOI surface by in situ growth, whereas the addition of Au further improved the photoelectric conversion efficiency and could link more antibodies. The three-dimensional (3D) ordered sheet-like network array structure and BiOI/Bi2S3/Au ternary nanosheet arrays showed stable and high photoelectric signal output and no significant difference in signals across different batches under visible light excitation. The fabricated immunosensor has a sensitive response to the target detection marker cTnI in a wide linear range of 500 fg/mL to 50 ng/mL, and the detection limit was 32 fg/mL, demonstrating good stability and selectivity. This work not only shows the great application potential of ternary heterojunction arrays in the field of PEC immunosensors but also provides a useful exploration for improving the stability of immunosensors.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Troponina I , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Ouro/química , Imunoensaio/métodos , Limite de Detecção , Troponina I/química , Troponina I/imunologia , Bismuto/química
3.
Langmuir ; 40(12): 6515-6523, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38466089

RESUMO

Photocatalysis represents an effective technology for environmental remediation. Herein, a series of Zn-doped BiOBr hollow microspheres are synthesized via one-pot solvothermal treatment of bismuth nitrate and dodecyl ammonium bromide in ethylene glycol along with a calculated amount of zinc acetate. Whereas the materials morphology and crystal structure remain virtually unchanged upon Zn-doping, the photocatalytic performance toward the degradation of ciprofloxacin is significantly improved under visible light irradiation. This is due to the formation of a unique band structure that facilitates the separation of photogenerated electron-hole pairs, reduced electron-transfer resistance, and enhanced electron mobility and carrier concentration. The best sample consists of a Zn doping amount of 1%, which leads to a 99.2% degradation rate of ciprofloxacin under visible photoirradiation for 30 min. The resulting photocatalysts also exhibit good stability and reusability, and the degradation intermediates exhibit reduced cytotoxicity compared to ciprofloxacin. These results highlight the unique potential of BiOBr-based photocatalysts for environmental remediation.


Assuntos
Antibacterianos , Zinco , Antibacterianos/farmacologia , Microesferas , Luz , Bismuto/química , Ciprofloxacina , Catálise
4.
Int J Biol Macromol ; 265(Pt 1): 130797, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38479662

RESUMO

In recent years, photocatalytic technology has been introduced to develop a new kind antimicrobial agents fighting antibiotic abusing and related drug resistance. The efforts have focused on non-precious metal photocatalysts along with green additives. In the present work, a novel bis-S heterojunctions based on the coupling of polysaccharide (CS) and bismuth-based MOF (CAU-17) s synthesized through a two-step method involving amidation reaction under mild conditions. The as prepared photocatalyst literally extended the light response to the near-infrared region. Owing to its double S-type heterostructure, the lifetime of the photocarriers is significantly prolonged and the redox capacity are enhanced. As a result, the as prepared photocatalyst indicated inhibition up to 99.9 % under 20 min of light exposure against Gram-positive (S. aureus) and Gram-negative (E. coli) bacteria as well as drug-resistant bacteria (MRSA). The outstanding photocatalytic performance is attributed to the effective charge separation and migration due to the unique double S heterostructure. Such a double S heterostructure was confirmed through transient photocurrent response, electrochemical impedance spectroscopy tests and electron spin resonance measurements. The present work provides a basis for the simple synthesis of high-performance heterojunction photocatalytic inhibitors, which extends the application of CAU-17 in environmental disinfection and wastewater purification.


Assuntos
Quitosana , Estruturas Metalorgânicas , Bismuto/química , Escherichia coli , Quitosana/farmacologia , Estruturas Metalorgânicas/farmacologia , Staphylococcus aureus , Catálise
5.
Environ Sci Pollut Res Int ; 31(15): 23228-23246, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38413524

RESUMO

Non-uniform, non-spherical bismuth oxide deposited on titanium vanadium oxide (3%-BVT1) was successfully synthesized via co-precipitation method and assessed for visible light degradation of aqueous diclofenac. The synthesized photocatalysts were characterized using X-ray diffraction, diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and high-resolution transmission electron microscopy. Up to 80.7% diclofenac degradation was observed with a significant increment in reaction rate compared to commercially available Degussa P25 (kapp = 0.0013 → 0.0083 min-1) achieved within 3 h treatment time under optimized parameters of diclofenac concentration (10 mg L-1), catalyst loading (0.1 g L-1), and pH (5). The enhanced photocatalysis could be due to electron-hole separation and contribution of powerful oxidative species •OH > O2•- > h+ > > e-. The recyclability experiments indicate that 3%-BVT1 retained its efficiency up to 74.1% over five reaction cycles. Gas chromatography-mass spectrometry analysis indicated the formation of several transformation products during the degradation pathway. The studies of interfering ions depicted mild interference by sulfates, while interference by phosphates and nitrates was negligible during photocatalytic process, i.e., 70, 78.01, and 78.43% for the selected concentrations of 50, 25, and 40 mg L-1 as per their maximum concentrations detected in the natural wastewaters. Thus, 3%-BVT1 is a potential versatile candidate to treat various organic pollutants including pharmaceuticals.


Assuntos
Diclofenaco , Vanádio , Titânio/química , Luz , Bismuto/química , Água , Catálise
6.
Chemistry ; 30(22): e202304216, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38356034

RESUMO

Bismuth is a xenobiotic metal with a high affinity to sulfur that is used in a variety of therapeutic applications. Bi(III) induces the cysteine-rich metallothionein (MT), a protein known to form two-domain cluster structures with certain metals such as Zn(II), Cd(II), or Cu(I). The binding of Bi(III) to MTs has been previously studied, but there are conflicting reports on the stoichiometry and binding pathway, which appear to be highly dependent on pH and initial metal-loading status of the MT. Additionally, domain specificity has not been thoroughly investigated. In this paper, ESI-MS was used to determine the binding constants of [Bi(EDTA)]- binding to apo-MT1a and its individual αMT fragment. The results were compared to previous experiments using ßMT1a and ßαMT3. Domain specificity was investigated using proteolysis methods and the initial cooperatively formed Bi2MT was found to bind to cysteines that spanned across the traditional metal binding domain regions. Titrations of [Bi(EDTA)]- into Zn7MT were performed and were found to result in a maximum stoichiometry of Bi7MT, contrasting the Bi6MT formed when [Bi(EDTA)]- was added to apo-MT. These results show that the initial structure of the apo-MT determines the stoichiometry of new incoming metals and explains the previously observed differences in stoichiometry.


Assuntos
Bismuto , Cisteína , Humanos , Ácido Edético , Bismuto/química , Cisteína/química , Metalotioneína/química , Zinco/química , Ligação Proteica , Cádmio/química , Sítios de Ligação
7.
J Colloid Interface Sci ; 662: 171-182, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38341940

RESUMO

The physical property tuning of nanomaterials is of great importance in energy, medicine, environment, catalysis, and other fields. Topochemical synthesis of nanomaterials can achieve precise control of material properties. Here, we synthesized a kind of element-doped bismuth-based nanomaterial (BOS) by topochemical-like synthesis and used it for the phototherapy of tumors. In this study, we employed bismuth fluoride nanoflowers as a template and fabricated element-doped bismuth oxide nanoflowers by reduction conditions. The product is consistent with the precursor in crystal structure and nanomorphology, realizing topochemical-like synthesis under mild conditions. BOS can generate reactive oxygen species, consume glutathione, and perform photothermal conversion under 730 nm light irradiation. In vitro and in vivo studies demonstrate that BOS could suppress tumor growth by inducing apoptosis and ferroptosis through phototherapy. Therefore, this study offers a general regulation method for tuning the physical properties of nanomaterials by using a topochemical-like synthesis strategy.


Assuntos
Neoplasias da Mama , Nanoestruturas , Neoplasias , Fotoquimioterapia , Humanos , Feminino , Neoplasias da Mama/radioterapia , Bismuto/química , Fototerapia/métodos , Neoplasias/tratamento farmacológico , Nanoestruturas/química , Linhagem Celular Tumoral
8.
Chemosphere ; 352: 141353, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38307337

RESUMO

The release of industrial effluents, comprising of organic dyes, antibiotics, and heavy metals poses substantial environmental and ecological threats. Among the different approaches, the utilization of heterogeneous photocatalysis based on semiconducting metal oxides is of paramount important to removal of organic ( MB dye and TC antibiotic) and inorganic pollutants ( Cr (VI) ) in wastewater. In this work, a new approach for creating type-II heterojunction photocatalysts named xNiCo2O4/BiVO4 or BNC is suggested. The as-prepared samples were thoroughly examined by means of several sophisticated analytical tools to investigate their physicochemical properties. These composites were utilized in the decomposition of MB dye, TC drug and the reduction of Cr (VI) under visible light irradiation. According to the findings, the creation of type-II heterojunction at BiVO4-NiCo2O4 interface greatly improved charge transportation while successfully preventing electron-hole recombination. Among the various composites studied, BNC-2 demonstrated an enhanced photocatalytic activity towards degradation of MB and TC, which were found to be 91 % over a period of 150 min and 95 % within only 60 min, respectively. Moreover, the photocatalytic reduction of Cr (VI) was accomplished 96 % within just 25 min. Additionally, it is discovered that BNC-2 displayed promising photostability and recyclability with a retention of >90 % after five consecutive cycles. The enhanced photocatalytic activity of BNC-2 is evidently attributed to the expedited separation and transfer of charges, as proven by photocurrent measurement, photoluminescence and electrochemical impedance spectroscopy analyses. Hence, the current amalgamation of NiCo2O4 and BiVO4 heterojunction composite has paved novel paths towards photocatalytic removal of organic as well as inorganic contaminants.


Assuntos
Bismuto , Poluentes Ambientais , Bismuto/química , Luz , Antibacterianos , Óxidos/química
9.
Chemosphere ; 346: 140585, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38303393

RESUMO

In this study, we prepared and tested a carbon-modified, Fe-loaded bismuth oxychloride (Fe-BiOCl/CS) photocatalyst for photocatalytic degradation of perfluorooctane sulfonate (PFOS). Structural analyses revealed a (110) facet-dominated sheet-type BiOCl crystal structure with uniformly distributed Fe and confirmed carbon modification of the photocatalyst. The presence of d-glucose facilitated the growth control of BiOCl particles and enhanced the adsorption of PFOS via added hydrophobic interaction. Adsorption kinetic and equilibrium tests showed rapid uptake rates of PFOS and high adsorption capacity with a Langmuir Qmax of 1.51 mg/g. When used for directly treating PFOS in solution, Fe-BiOCl/CS was able to mineralize or defluorinate 83% of PFOS (C0 = 100 µgL-1) under UV (254 nm, intensity = 21 mW cm-2) in 4 h; and when tested in a two-step mode, i.e., batch adsorption and subsequent photodegradation, Fe-BiOCl/CS mineralized 65.34% of PFOS that was pre-concentrated in the solid phase under otherwise identical conditions; while the total degradation percentages of PFOS were 83.48% and 80.50%, respectively, for the two experimental modes. The photoactivated electrons and/or hydrated electrons and superoxide radicals primarily initiated the desulfonation of PFOS followed by decarboxylation and defluorination, through a stepwise chain-subsiding mechanism. The elevated photocatalytic activity can be attributed to the effective separation of e-/h+ pairs facilitated by the (110) interlayer electrostatic field, Fe doping, and the presence of oxygen vacancies. This work reveals the potential of carbon-modified and Fe-co-catalyzed BiOCl for concentrating and degrading PFOS and possibly other persistent organic pollutants.


Assuntos
Ácidos Alcanossulfônicos , Carbono , Fluorocarbonos , Poluentes Químicos da Água , Poluentes Químicos da Água/química , Fotólise , Bismuto/química , Água
10.
Sci Total Environ ; 915: 170125, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38242469

RESUMO

Bacterial infections pose a seriously threat to the safety of the environment and human health. In particular, the emergence of drug-resistant pathogens as a result of antibiotic abuse and high trauma risk has rendered conventional therapeutic techniques insufficient for treating infections by these so-called "superbugs". Therefore, there is an urgent need to develop highly efficient and environmentally-friendly antimicrobial agents. Bismuth-based nanomaterials with unique structures and physicochemical characteristics have attracted considerable attention as promising antimicrobial candidates, with many demonstratingoutstanding antibacterial effects upon being triggered by broad-spectrum light. These nanomaterials have also exhibited satisfactory energy band gaps and electronic density distribution with improved photonic properties for extensive and comprehensive applications after being modified through various engineering methods. This review summarizes the latest research progress made on bismuth-based nanomaterials with different morphologies, structures and compositions as well as the different methods used for their synthesis to meet their rapidly increasing demand, especially for antibacterial applications. Moreover, the future prospects and challenges regarding the application of these nanomaterials are discussed. The aim of this review is to stimulate interest in the development and experimental transformation of novel bismuth-based nanomaterials to expand the arsenal of effective antimicrobials.


Assuntos
Anti-Infecciosos , Infecções Bacterianas , Nanocompostos , Humanos , Bismuto/química , Antibacterianos/química
11.
Sci Rep ; 14(1): 1591, 2024 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-38238361

RESUMO

Since quinolone is a kind of synthetic broad-spectrum antibacterial drugs, with the widespread use of this class of antibiotics, the risk and harm to human health have been attendant to the sewage containing quinolones which are discharged into the environment. Photocatalysis is considered as a promising technology for antibiotic degradation for its strong redox properties and reaction rate. As a metal oxidizing substance, Bismuth vanadate (BiVO4) is such a popular and hot material for the degradation of organic pollutants recently due to its good photocatalytic activity and chemical stability. Numerous studies have confirmed that BiVO4 composites can overcome the shortcomings of pure BiVO4 and cleave the main structure of quinolone under photocatalytic conditions. This paper mainly outlines the research progress on the preparation of BiVO4 composites and the degradation of quinolone antibiotics from the perspective of improving the catalysis and degrading the efficiency mechanism of BiVO4 composites.


Assuntos
Antibacterianos , Quinolonas , Humanos , Antibacterianos/química , Bismuto/química , Vanadatos/química , Catálise , Luz
12.
J Biochem Mol Toxicol ; 38(1): e23548, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37867459

RESUMO

Four novel antimony (III) and bismuth(III) complexes of the kind Cl-Sb-O-C(OR)-CH(CH3 )C-NH-(CH2 )2 -NH-C(CH3 )CH:C(OR)-O [where R = -CH3 , M = Sb (1a); R = -C2 H5 , M = Sb (1b); R = -CH3, M = Bi (1c); R = -C2 H5 , M = Bi (1d)] were successfully prepared by reacting antimony(III)chloride and bismuth(III)chloride with sodium salt of ß-enamino esters in 1:1 stoichiometry, which were further structurally characterized by physicochemical and IR, 1 H, 13 C NMR spectral and mass spectrometry. Structural analysis revealed that all four derivatives of both antimony and bismuth display octahedarl geometry which has been optimized through computational studies. These derivatives along with their parent ligands were subsequently assayed in vitro for antibacterial (Bacillus subtilis, Pseudomonas aeruginosa) and antifungal (Aspergillus niger and Candida albicans) activities. Synthesized complexes were more efficacious in terms of biological activities as compared to parent ligands Further synthesized compounds were evaluated for their in vitro cytotoxic activity against lung cancer cell line A549 using MTT method. IC50 value for all four complexes was determined and all of them are found active. Computational studies of the representative complexes have been done using B3LYP/631-G* basis sets to provide optimized geometry.


Assuntos
Anti-Infecciosos , Antineoplásicos , Antimônio/farmacologia , Bismuto/farmacologia , Bismuto/química , Teoria da Densidade Funcional , Cloretos , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Testes de Sensibilidade Microbiana
13.
Environ Sci Pollut Res Int ; 31(3): 4747-4763, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38105325

RESUMO

Semiconductor photocatalysis is the most efficient advanced oxidation processes for wastewater treatment. A new carbon-based photocatalyst bismuth oxide/multi-walled carbon nanotube (Bi2O3/MWCNT) nanocomposite has a considerable impact on improving photocatalytic performance. Bi2O3/MWCNTs (BMC) nanocomposite was prepared through the hydrothermal processing with 2.5, 5, 7.5 and 10 wt% of MWCNTs. The prepared photocatalysts have been thoroughly examined by various techniques. The X-ray diffraction confirmed the prepared photocatalyst as α-Bi2O3 with high crystallinity. The band gap of Bi2O3 and BMC 7.5 nanocomposite was found to be 2.41 and 1.94 eV. The prepared photocatalyst revealed smooth and porous merged flower-like structure with respect to the addition of MWCNTs. The model pollutant chromium(VI) (Cr(VI)) has been used to check the reduction efficiency of the prepared photocatalyst under solar irradiation. It was found that BMC 7.5 nanocomposite showed enhanced photocatalytic metal ion reduction (87.48%) compared to pristine Bi2O3 (69.29%). The preliminary photocatalytic Cr(VI) ion reduction experiments were carried to determine the photoreduction efficiency of pristine bismuth oxide and bismuth MWCNT nanocomposite. The kinetic study on Cr(VI) ion reduction obeyed pseudo-first-order rate kinetics for both the prepared photocatalysts. The efficiency of the photocatalysts was further analysed by reusing the same up to 3 cycles without loss of the efficacy.


Assuntos
Nanocompostos , Nanotubos de Carbono , Luz , Bismuto/química , Nanotubos de Carbono/química , Cromo/química , Catálise
14.
Chemosphere ; 350: 141012, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38145845

RESUMO

The increasing pollution of water bodies with organic contaminants, including antibiotics, has become a significant environmental concern. In this study, a noble-metal-free alternative, NiCo bimetal cocatalyst, was synthesized and applied to enhance the photocatalytic degradation of the antibiotic tetracycline (TC) using BiVO4 as the photocatalyst under the visible spectrum. The NiCo-BiVO4 nanocomposite exhibited improved visible light absorption, reduced recombination rate of charge carriers, and enhanced electrochemical properties. The photocatalytic degradation of TC was significantly enhanced by the NiCo bimetal modification, with the 2 wt% NiCo-BiVO4 nanocomposite achieving an 87.2% degradation of TC and 82% Total Organic Carbon (TOC) removal within 120 min. The degradation kinetics of TC (target compound) followed a first-order reaction, with photogenerated electrons and holes identified as the primary active species responsible for the degradation process. The recyclability of the catalyst was also demonstrated for multiple runs, indicating its stability. Furthermore, the pathway of TC degradation by 2 wt% NiCo-BiVO4 nanocomposite was proposed based on the detected intermediate products using LC-MS analysis. This study provides a promising approach for developing efficient, noble-metal-free photocatalysts to remove organic contaminants from water sources.


Assuntos
Nanocompostos , Água , Fotólise , Bismuto/química , Antibacterianos/química , Tetraciclina , Luz , Catálise
15.
Anal Methods ; 15(47): 6541-6550, 2023 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-37990986

RESUMO

This work describes the development of a membraneless, self-powered immunosensor exploiting a photoelectrochemical system based on two photoelectrodes for cardiac troponin I (cTn). An electrode based on CaBi2Ta2O9 combined with bismuth oxyiodides (BiOI/Bi4O5I2/Bi5O7I) was modified with the cTnI antibody (anti-cTnI) and applied in a photoelectrochemical cell as a photoanode. To perform the cTnI detection exploiting a self-powered photoelectrochemical setup, the immunosensor (anti-cTnI/BiOI/Bi4O5I2/Bi5O7I/CaBi2Ta2O9/FTO) was coupled to a photoelectrochemical cell containing a photocathode based on CuBi2O4 (CBO/FTO) for zero-biased photoelectrochemical immunosensing of cardiac troponin I (cTnI) biomarker. For comparison purposes, the photoanode was applied for cTnI detection in a three-electrode electrochemical cell. The spectroscopic, structural, and morphological characteristics of the photoelectrochemical (PEC) materials were evaluated using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD). Electrochemical impedance spectroscopy (EIS) measurements were performed in the presence and absence of light to investigate the effects of photons on the charge transfer resistance of the photoanode. The influence of the cTnI biomarker on the photoelectrochemical response of the anti-cTnI antibody-modified photoelectrochemical platform (anti-cTnI/BiOI/Bi4O5I2/Bi5O7I/CaBi2Ta2O9/FTO) was evaluated by measuring the photocurrent of the system. The immunosensor presented a linear response ranging from 1 pg mL-1 to 200 ng mL-1 as well as a mean recovery percentage between 95.7% and 108.0% in real human serum samples for the cTnI biomarker.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Humanos , Técnicas Eletroquímicas/métodos , Imunoensaio/métodos , Bismuto/química , Técnicas Biossensoriais/métodos , Troponina I , Biomarcadores , Dioxigenase FTO Dependente de alfa-Cetoglutarato
16.
Sci Rep ; 13(1): 17847, 2023 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-37857696

RESUMO

The environmental-friendly hydrothermal method has been carried out to synthesize Bi2WO6 and g-C3N4/PVP doped Bi2WO6 nanorods (NRs) by incorporating different concentrations of graphitic carbon nitride (g-C3N4) as well as a specified quantity of polyvinylpyrrolidone (PVP). Bi2WO6 doped with g-C3N4 provides structural and chemical stability, reduces charge carriers, degrades dyes, and, owing to lower bandgap energy, is effective for antibacterial, catalytic activity, and molecular docking analysis. The purpose of this research is the treatment of polluted water and to investigate the bactericidal behavior of a ternary system. The catalytic degradation was performed to remove the harmful rhodamine B (RhB) dye using NaBH4 in conjunction with prepared NRs. The specimen compound demonstrated antibacterial activity against Escherichia coli (E. coli) at both high and low concentrations. Higher doped specimens of g-C3N4/PVP-doped Bi2WO6 exhibited a significant improvement in efficient bactericidal potential against E. coli (4.55 mm inhibition zone). In silico experiments were carried out on enoyl-[acylcarrier-protein] reductase (FabI) and ß-lactamase enzyme for E. coli to assess the potential of Bi2WO6, PVP doped Bi2WO6, and g-C3N4/PVP-doped Bi2WO6 NRs as their inhibitors and to justify their possible mechanism of action.


Assuntos
Bismuto , Povidona , Simulação de Acoplamento Molecular , Povidona/farmacologia , Bismuto/química , Luz , Corantes/farmacologia , Escherichia coli , Antibacterianos/farmacologia , Antibacterianos/química
17.
Chemosphere ; 345: 140414, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37827460

RESUMO

The rare earth metal, samarium (Sm3+) doped bismuth tungstate (Bi2WO6) nanoparticles were prepared by a one-pot hydrothermal method. The powder X-ray diffraction (XRD) analysis confirmed the formation of Bi2WO6 with an orthorhombic crystal structure. The crystallite size of Bi2WO6 decreased from 20.73 to 9.25 nm as the Sm substitution in the W lattice increased. The vibrational modes of W-O, Bi-O, and Sm-O were identified in the range of 500-900 cm-1. The optical bandgap of Sm3+ doped Bi2WO6 nanoparticles increased from 2.86 to 2.95 eV with higher Sm doping levels. The surface morphology revealed the formation of flower-like sheets in the Sm3+ doped bismuth tungstate. The energy dispersive X-ray (EDX) spectrum of Sm3+ doped Bi2WO6 nanoparticles confirmed the presence of Sm, Bi, W, and O without any other impurities. The small peak detected at 1082.14 eV in the survey scan of Sm3+ doped Bi2WO6 nanoparticles belonged to Sm3d. In the photocatalytic degradation of direct blue 15 (DB15) under visible light irradiation, the efficiency of the nanoparticles increased with higher Sm3+ concentration. The obtained results demonstrated that the Sm-Bi2WO6 nanosheets could provide an effective and sustainable solution for treating the wastewater containing direct blue 15 dye.


Assuntos
Samário , Purificação da Água , Samário/química , Bismuto/química , Luz , Catálise
18.
J Environ Manage ; 345: 118772, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37597373

RESUMO

This work investigates the use of novel BiOI@ZIF-8 nanocomposite for the removal of acetaminophen (Ace) from synthetic wastewater. The samples were analyzed using FTIR, XRD, XPS, DRS, PL, FESEM-EDS, and ESR techniques. The effects of the loading capacity of ZIF-8 on the photocatalytic oxidation performance of bismuth oxyiodide (BiOI) were studied. The photocatalytic degradation of Ace was maximized by optimizing pH, reaction time and the amount of photocatalyst. On this basis, the removal mechanisms of the target pollutant by the nanocomposite and its photodegradation pathways were elucidated. Under optimized conditions of 1 g/L of composite, pH 6.8, and 4 h of reaction time, it was found that the BiOI@ZIF-8 (w/w = 1:0.01) nanocomposite exhibited the highest Ace removal (94%), as compared to that of other loading ratios at the same Ace concentration of 25 mg/L. Although this result was encouraging, the treated wastewater still did not satisfy the required statutory of 0.2 mg/L. It is suggested that the further biological processes need to be adopted to complement Ace removal in the samples. To sustain its economic viability for wastewater treatment, the spent composite still could be reused for consecutive five cycles with 82% of regeneration efficiency. Overall, this series of work shows that the nanocomposite was a promising photocatalyst for Ace removal from wastewater samples.


Assuntos
Acetaminofen , Nanocompostos , Bismuto/química , Águas Residuárias , Raios Ultravioleta
19.
Chemosphere ; 339: 139678, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37527742

RESUMO

Organic pollutants pose a significant threat to water safety, and their degradation is of paramount importance. Photocatalytic technology has emerged as a promising approach for environmental remediation, and Bismuth ferrite (BiFeO3) has been shown to exhibit remarkable potential for photocatalytic degradation of water pollutants, with its excellent crystal structure properties and visible light photocatalytic activity. This review presents an overview of the crystal properties and photocatalytic mechanism of perovskite bismuth ferrite (BiFeO3), as well as a summary of various strategies for enhancing its efficiency in photocatalytic degradation of organic pollutants. These strategies include pure phase preparation, microscopic modulation, composite modification of BiFeO3, and the integration of Fenton-like reactions and external field-assisted methods to improve its photocatalytic performance. The review emphasizes the impact of each strategy on photocatalytic enhancement. By providing comprehensive strategies for improving the efficiency of BiFeO3 photocatalysis, this review inspires new insights for efficient degradation of organic pollutants using BiFeO3 photocatalysis and contributes to the development of photocatalysis in environmental remediation.


Assuntos
Bismuto , Poluentes Ambientais , Bismuto/química , Catálise , Poluentes Ambientais/química
20.
ACS Nano ; 17(16): 15568-15589, 2023 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-37531599

RESUMO

Due to the increasing antibiotic resistance and the lack of broad-spectrum antibiotics, there is an urgent requirement to develop fresh strategies to combat multidrug-resistant pathogens. Herein, defect-rich bismuth molybdate heterojunctions [zero-dimensional (0D) Bi4MoO9/two-dimensional (2D) Bi2MoO6, MBO] were designed for rapid capture of bacteria and synergistic photocatalytic sterilization. The as-prepared MBO was experimentally and theoretically demonstrated to possess defects, heterojunctions, and irradiation triple-enhanced photocatalytic activity for efficient generation of reactive oxygen species (ROS) due to the exposure of more active sites and separation of effective electron-hole pairs. Meanwhile, dopamine-modified MBO (pMBO) achieved a positively charged and rough surface, which conferred strong bacterial adhesion and physical penetration to the nanosheets, effectively trapping bacteria within the damage range and enhancing ROS damage. Based on this potent antibacterial ability of pMBO, a multifunctional hydrogel consisting of poly(vinyl alcohol) cross-linked tannic acid-coated cellulose nanocrystals (CPTB) and pMBO, namely CPTB@pMBO, is developed and convincingly effective against methicillin-resistant Staphylococcus aureus in a mouse skin infection model. In addition, the strategy of combining a failed beta-lactam antibiotic with CPTB@pMBO to photoinactivation with no resistance observed was developed, which presented an idea to address the issue of antibiotic resistance in bacteria and to explore facile anti-infection methods. In addition, CPTB@pMBO can reduce excessive proteolysis of tissue and inflammatory response by regulating the expression of genes and pro-inflammatory factors in vivo, holding great potential for the effective treatment of wound infections caused by drug-resistant bacteria.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Animais , Camundongos , Bismuto/farmacologia , Bismuto/química , Hidrogéis/farmacologia , Espécies Reativas de Oxigênio/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química
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