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1.
J Mater Chem B ; 12(3): 678-690, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38116646

RESUMEN

The present study introduces Fe3O4-coated lapatinib-labeled 153Sm nanoparticles (denoted as Fe3O4@lapatinib-153Sm) as a promising avenue for advancing breast cancer treatment. The radiolabeled nanoparticles combine various attributes, offering enhanced therapeutic precision. The integration of lapatinib confers therapeutic effects and targeted delivery. The inherent magnetic characteristics of Fe3O4 nanoparticles contribute to improved imaging contrast and targeted localization. Incorporating the gamma-emitting 153Sm isotope permits single-photon emission computed tomography imaging and radiation dose evaluation, while its beta-emitting nature ensures targeted cancer cell eradication. The synthesis of Fe3O4@lapatinib-153Sm was meticulously optimized by investigating the effects of parameters on radiolabeling efficiency. Physicochemical attributes were scrutinized using several analytical techniques. In-depth in vivo assessment evaluated the biocompatibility, toxicity, and biodistribution in a murine model, illuminating clinical utility. Optimal conditions (153SmCl3 concentration of 10 mCi mL-1, pH 7.4, a reaction time of 30 min, and a temperature of 25 °C) achieved >99% labeling efficiency and radiochemical purity. The TEM analysis indicated that the diameter of Fe3O4@lapatinib-153Sm nanoparticles ranged from 10 to 40 nm. Vibrating-sample magnetometry verified their superparamagnetic behaviour with a saturation magnetization of 41.4 emu g-1. The synthesized radiopharmaceutical exhibited high sterility and in vitro stability. Acute toxicity studies showed the mild effects of Fe3O4@lapatinib-153Sm at a dose of 20 mCi kg-1, with no observed mortality. Notably, lesions from Fe3O4@lapatinib-153Sm use recovered naturally over time. Radiation doses below 20 mCi kg-1 were recommended for clinical trials. The biodistribution study in BT474 xenograft mice revealed rapid clearance of Fe3O4@lapatinib-153Sm within 48 h. Significant accumulation occurred in the liver, spleen, and tumor tissue, while minimal accumulation was found in other tissues. Future steps involve studying biocorona formation and therapeutic efficacy on tumour models, refining its clinical potential.


Asunto(s)
Neoplasias de la Mama , Nanopartículas , Humanos , Animales , Ratones , Femenino , Lapatinib , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/tratamiento farmacológico , Distribución Tisular , Control de Calidad
2.
Heliyon ; 9(10): e20466, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37810813

RESUMEN

The persistent presence of organic pollutants like dyes in water environment necessitates innovative approaches for efficient degradation. In this research, we developed an advanced hybrid catalyst by combining metal oxides (Cu2O, Fe3O4) with UiO-66, serving as a heterogeneous Fenton catalyst for for efficient RB19 breakdown in water with H2O2. The control factors to the catalytic behavior were also quantified by machine learning. Experimental results show that the catalytic performance was much better than its individual components (P < 0.05 & non-zero 95% C.I). The improved catalytic efficiency was linked to the occurrence of active metal centers (Fe, Cu, and Zr), with Cu(I) from Cu2O playing a crucial role in promoting increased production of HO•. Also, UiO-66 served as a catalyst support, attracting pollutants to the reaction center, while magnetic Fe3O4 aids catalyst recovery. The optimal experimental parameters for best performance were pH at 7, catalyst loading of 1.6 g/L, H2O2 strength of 0.16 M, and reaction temperature of 25 °C. The catalyst can be magnetically separated and regenerated after five recycling times without significantly reducing catalytic activity. The reaction time and pH were ranked as the most influencing factors on catalytic efficiency via Random Forest and SHapley Additive exPlanations models. The findings show that developed catalyst is a suitable candidate to remove dyes in water by Fenton heterogeneous reaction.

3.
Chemosphere ; 336: 139265, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37339705

RESUMEN

One of the current directions for sustainable development is to use waste resources to create materials that reduce environmental pollution. In this study, multi-walled carbon nanotubes (MWCNT) and their oxygen-functionalized forms (HNO3/H2SO4-oxidized MWCNT, NaOCl-oxidized MWCNT, and H2O2-oxidized MWCNT) were first synthesized from activated carbon (AC) derived from rice husk waste. A comprehensive comparison of the morphological and structural properties of these materials was conducted using FT-IR, BET, XRD, SEM, TEM, TGA, Raman spectroscopy, and surface charge analysis. The morphology study suggests that the synthesized MWCNTs have an average outer and inner diameter of about 40 and 20 nm, respectively. Additionally, the NaOCl-oxidized MWCNT possesses the largest interspaces between nanotubes, while the HNO3/H2SO4-oxidized CNT has the most oxygen-functional groups, including -COOH, (Ar)-OH, and C-OH. The adsorption capacities of these materials were also compared for the removal of benzene and toluene. Experimental results have shown that while porosity is the primary factor governing the benzene and toluene adsorption onto AC, functionalization degree and surface chemical characteristics are the determining factors in the adsorption capacity of the as-prepared MWCNTs. The adsorption capacity of these aromatic compounds in an aqueous solution increases in the following order: AC < MWCNT < HNO3/H2SO4-oxidized MWCNT < H2O2-oxidized MWCNT < NaOCl-oxidized MWCNT, and in all cases, toluene is more readily adsorbed than benzene under similar adsorption conditions. Wherein the uptake of both pollutants by the prepared adsorbents in this study is best described by the Langmuir isotherm and obeys the pseudo-second-order kinetic model. The adsorption mechanism was discussed in a detailed manner.


Asunto(s)
Nanotubos de Carbono , Oryza , Contaminantes Químicos del Agua , Tolueno/análisis , Benceno/análisis , Nanotubos de Carbono/química , Adsorción , Oxígeno/análisis , Espectroscopía Infrarroja por Transformada de Fourier , Peróxido de Hidrógeno , Cinética , Contaminantes Químicos del Agua/análisis
4.
Chemosphere ; 313: 137352, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36436577

RESUMEN

In this study, the kinetic degradation of several typical organic pollutants was performed on a synthetic electrode (Ti/SnO2-Sb/Co-ßPbO2). The surface structure and the electrochemical properties of the prepared electrode were investigated, confirming the successful preparation of the electrode using an electrochemical deposition method. The outer layer (Co-ßPbO2) played an important role in reducing the resistance of the electrode and improving its degradation efficiency. The results showed that indigo carmine (IC), p-nitrosodimethylaniline (RNO), and clothianidin (CLO) were effectively degraded within 20 min of electrolysis. Their degradation in the electrochemical process followed the first-order kinetic model with the degradation rate constant of IC being higher than that of RNO and CLO. This was proved by the difference in the reactivity of the target pollutants toward oxidizing radicals (i.e., •OH, SO4•-, and Cl•). Their second-order rate constant towards radicals were in the range of 109 - 1010 M-1 s-1 with the highest value being that for IC: k·OH,IC = 15.1 × 109 M-1 s-1 and [Formula: see text]  = 7.4 × 109 M-1 s-1. The study calculated the contribution of some oxidizing species, including direct electron transfer (DET), •OH, SO4•-, and other reactive oxygen species (ROS). Solution pH, supporting electrolyte, and water matrix affected the degradation efficiency of pollutants and the contribution of the oxidizing species. Br- and I- ions enhanced the degradation rate of organic pollutants, while Fe2+, HCO3-, and humic acid (HA) reduced it. In addition, the toxicity, total organic carbon (TOC) removal, mineralization current efficiency (MCE), energy consumption, recyclability and stability of the prepared electrode were studied, suggesting that the prepared Ti/SnO2-Sb/Co-ßPbO2 is a good candidate for treating organic pollutants using the electrochemical oxidation process.


Asunto(s)
Contaminantes Químicos del Agua , Agua , Carmin de Índigo , Titanio/química , Electrodos , Contaminantes Químicos del Agua/química , Oxidación-Reducción
5.
Environ Sci Pollut Res Int ; 30(28): 71543-71553, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33772471

RESUMEN

In this study, a ternary magnetically separable nanocomposite of silver nanoparticles (AgNPs) embedded in magnetic graphene oxide (Ag/Fe3O4@GO) was designed and synthesized. Beta-cyclodextrin was used as a green reducing and capping agent for decorating of AgNPs on Fe3O4@GO. The fabricated material was characterized using X-ray diffractometry, Fourier transform infrared spectroscopy, scanning electron microscopy, vibrating sample magnetometry, and energy-dispersive X-ray spectroscopy. The catalytic properties of the prepared Ag/Fe3O4@GO for the reduction of 4-nitrophenol (4-NP) and methylene blue (MB) dye with sodium borohydride were investigated in detail. The morphological and structural studies revealed that Fe3O4 and AgNPs with a mean size of 12 nm were uniformly distributed on the GO sheet at high densities. The catalytic tests showed that Ag/Fe3O4@GO exhibited an ultrafast catalytic reduction of 4-NP and MB with a reduction rate constant of 0.304 min-1 and 0.448 min-1, respectively. Moreover, the catalyst demonstrated excellent stability and reusability, as evidenced by the more than 97% removal efficiency maintained after five reuse cycles. The Ag/Fe3O4@GO catalyst could be easily recovered by the magnetic separation due to the superparamagnetic nature of Fe3O4 with high saturated magnetization (45.7 emu/g). Besides, the formation of networking between the formed AgNPs and ß-CD through hydrogen bonding prevented the agglomeration of AgNPs, ensuring their high catalytic ability. The leaching study showed that the dissolution of Fe and Ag from Ag/Fe3O4@GO was negligible, indicating the environmental friendliness of the synthesized catalyst. Finally, the high catalytic performance, excellent stability, and recoverability of Ag/Fe3O4@GO make it a potential candidate for the reduction of organic pollutants in wastewater.


Asunto(s)
Nanopartículas del Metal , Nanopartículas del Metal/química , Azul de Metileno/química , Plata/química , Fenómenos Magnéticos , Catálisis
6.
RSC Adv ; 12(42): 27116-27124, 2022 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-36276021

RESUMEN

In this study, gold nanoparticles (AuNPs) were synthesized via a green and environmentally-friendly approach and applied as a colorimetric probe for detecting Pb2+ ions in aqueous solution. Instead of toxic chemicals, Michelia tonkinensis (MT) seed extract was used for reducing Au3+ and stabilizing the formed AuNPs. The synthesis conditions, including temperature, reaction time, and Au3+ ion concentration, were optimized at 90 °C, 40 min, and 1.25 mM, respectively. The physicochemical properties of the produced MT-AuNPs were assessed by means of transmission electron microscopy, X-ray diffraction, field emission scanning electron microscopy, dynamic light scattering, and Fourier-transform infrared spectroscopy. The characterization results revealed that the MT-AuNPs exhibited a spherical shape with a size of about 15 nm capped by an organic layer. The colorimetric assay based on MT-AuNPs showed excellent sensitivity and selectivity toward Pb2+ ions with the limit of detection value of 0.03 µM and the limit of quantification of 0.09 µM in the linear range of 50-500 µM. The recoveries of inter-day and intra-day tests were 97.84-102.08% and 98.78-102.34%, respectively. The MT-AuNPs probe also demonstrated good and reproducible recoveries (98.71-101.01%) in analyzing Pb2+ in drinking water samples, indicating satisfactory practicability and operability of the proposed method.

7.
Chemosphere ; 308(Pt 1): 136182, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36037942

RESUMEN

Volatile organic compounds (VOCs) are a group of organic compounds that have a molecular structure containing carbon and their chemical properties allow them to be easily converted to steam and gas and remain for a long period of time and have diverse effects on the environment. The purpose of this study is determination of the concentration of VOCs such as alachlor, anthracene, benzene, bromoform, chloroform, heptachlor, isophorone, tetrachloroethylene, γ -chlordane, toluene, etc. in water matrices. The results showed that among studies conducted on VOCs, the concentration of tetrachloroethylene, m,p-xylene, and toluene were at the top in water matrices, and the lowest average concentrations were found in chloroform, anthracene, and butyl benzyl phthalate. In terms of VOC concentrations in water matrices, China was the most polluted country. Moreover, the data analysis indicated that China was the only country with carcinogenic risk. A Monte-Carlo simulation showed that although the averages obtained were comparable to the acceptable limits, for heptachlor, the maximum carcinogenic risk is achieved at a level that is slightly over the limit, only 25% from the population being exposed.


Asunto(s)
Contaminantes Atmosféricos , Tetracloroetileno , Compuestos Orgánicos Volátiles , Contaminantes Atmosféricos/análisis , Antracenos/análisis , Benceno/análisis , Carbono/análisis , China , Clordano/análisis , Cloroformo/análisis , Monitoreo del Ambiente/métodos , Heptacloro/análisis , Vapor/análisis , Tetracloroetileno/análisis , Tolueno/análisis , Compuestos Orgánicos Volátiles/análisis , Agua/análisis
8.
Chemosphere ; 303(Pt 3): 135202, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35667511

RESUMEN

In the present article, the disulfide tungsten/activated carbon derived from Eichhornia crassipes (WS2/AC) was synthesized by the hydrothermal process. The received materials were examined by X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray - mapping, and nitrogen adsorption/desorption isotherms. The morphology of WS2/AC was tailored to have a micro/meso/macro structure that facilized large electric conductivity and quick ion diffusion. The WS2/AC sample was used as an electrode modifier for developing an electrochemical sensor for salbutamol detection. WS2/AC exhibited excellent oxidation toward salbutamol. Through some optimized conditions, the electrochemical signal of the proposed sensor varied linearly to the salbutamol concentration ranging from 1 to 210 µM with a low LOD (detection limit) of 0.52 µM. The developed sensor showed several merits: easy producing, convenient usage, fabulous selectivity, and good repeatability as well as reproducibility. Finally, the suggested technique can be applied to determine salbutamol in people's biological fluid with satisfactory recoveries of 98.5-104.4% and without statistics different from standard HPLC.


Asunto(s)
Carbón Orgánico , Tungsteno , Albuterol , Técnicas Electroquímicas/métodos , Electrodos , Humanos , Límite de Detección , Reproducibilidad de los Resultados , Tungsteno/química
9.
Environ Chem Lett ; 20(4): 2629-2664, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35431714

RESUMEN

The release of pharmaceuticals into the environment induces adverse effects on the metabolism of humans and other living species, calling for advanced remediation methods. Conventional removal methods are often non-selective and cause secondary contamination. These issues may be partly solved by the use of recently-developped adsorbents such as molecularly imprinted polymers. Here we review the synthesis and application of molecularly imprinted polymers for removing pharmaceuticals in water. Molecularly imprinted polymers are synthesized via several multiple-step polymerization methods. Molecularly imprinted polymers are potent adsorbents at the laboratory scale, yet their efficiency is limited by template leakage and polymer quality. Adsorption performance of multi-templated molecularly imprinted polymers depends on the design of wastewater treatment plants, pharmaceutical consumption patterns and the population serviced by these wastewater treatment plants.

10.
Environ Res ; 212(Pt B): 113281, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35461847

RESUMEN

Biogenic gold nanoparticles (AuNPs) have been extensively studied for the catalytic conversion of nitrophenols (NP) into aminophenols and the colorimetric quantification of heavy metal ions in aqueous solutions. However, the high self-agglomeration ability of colloidal nanoparticles is one of the major obstacles hindering their application. In the present study, we offered novel biogenic AuNPs synthesized by a green approach using Cistanche deserticola (CD) extract as a bioreducing agent and stabilized on poly(styrene-co-maleic anhydride) (PSMA). The prepared Au@PSMA nanoparticles were characterized by various techniques (HR-TEM, SEAD, FE-SEM, DLS, TGA, XRD, and FTIR) and studied for two applications: the catalytic reduction of 3-NP by NaBH4 and the sensing detection of Pb2+ ions. The optimal conditions for the synthesis of AuNPs were investigated and established at 60 °C, 20 min, pH of 9, and 0.5 mM Au3+. Morphological studies showed that AuNPs synthesized by CD extract were mostly spherical with a mean diameter of 25 nm, while the size of polymer-integrated AuNPs was more than two-fold larger. Since PSMA acted as a matrix keeping the nanoparticles from coagulation and maintaining the optimal surface area, AuNPs integrated with PSMA showed higher catalytic efficiency with a faster reaction rate and lower activation energy than conventional nanoparticles. Au@PSMA could completely reduce 3-NP within 10 min with a rate constant of 0.127 min-1 and activation energy of 9.96 kJ/mol. The presence of PSMA also improved the stability and recyclability of AuNPs. Used as a sensor, Au@PSMA exhibited excellent sensitivity and selectivity for Pb2+ ions with a limit of detection of 0.03 µM in the linear range of 0-100 µM. The study results suggested that Au@PSMA could be used as a promising catalyst for the reduction of NP and the colorimetric sensor for detection of Pb2+ ions in aqueous environmental samples.


Asunto(s)
Oro , Nanopartículas del Metal , Colorimetría/métodos , Oro/química , Iones , Plomo , Maleatos , Anhídridos Maleicos , Nanopartículas del Metal/química , Nitrofenoles , Oxidación-Reducción , Extractos Vegetales , Poliestirenos
11.
Chemosphere ; 299: 134431, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35358564

RESUMEN

In this article, a system for synthesizing Y-90 glass microspheres (Y-90-GM) was successfully designed in the Da Lat nuclear reactor (Vietnam), and the therapeutic effects of Y-90-GM on mice liver cancer cell line Hep3B were studied. The effects of synthesis factors, including heating time, heating temperature, gas flow rate, sample conduit length and diameter, were investigated to establish the optimal parameters. The size and shape of Y-90-GM were checked by field emission scanning electron microscope, and the radioactivity measurement was performed on a dosimeter. The results indicated that the optimal conditions for the synthesis of Y-90-GM were determined as the heating temperature of 1600 °C, heating time of 2 h, conduit length and diameter of 50 cm and 3.6 cm, and gas/oxygen flow rate of 15 mph. The Y-90-GM samples obtained at the optimal parameters have a size of 18-30 µm with a density of 3.53 g cm-3 and a specific radioactivity of 630 mCi g-1. The results of the therapeutic study on mice liver cancer cell line Hep3B showed that after two weeks of treatment with Y-90-GM (1mCi/mouse), the tumor volume was reduced by about 30.7% and after 3 consecutive treatment cycles, the liver cancer tumor was completely reduced. It was demonstrated that Y-90-GM is promising radiopharmaceuticals in the treatment of liver cancer by the radioembolization method.


Asunto(s)
Embolización Terapéutica , Neoplasias Hepáticas , Animales , Línea Celular , Embolización Terapéutica/métodos , Vidrio , Neoplasias Hepáticas/metabolismo , Ratones , Microesferas , Radioisótopos de Itrio/uso terapéutico
12.
Chemosphere ; 297: 134116, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35227745

RESUMEN

Venlafaxine (denoted as VFX), a member of the most extensively prescribed antidepressants, is used to handle major depressive disorder, panic disorder and anxiety. This medication affects brain chemistry, which could cause an imbalance in depressed people. VFX and its metabolites, on the other hand, are pollutants in the water environment. Through movement and transformation in several procedures like adsorption, photolysis, hydrolysis and biodegradation, they have harmed living creatures, resulting in the enhancement of diverse active chemicals found in the environment. As a result, determining VFX at modest concentrations with excellent sensitivity, specificity and repeatability are critical. To quantify VFX, various analytical methodologies have been developed. Electroanalytical processes, on the other hand, have piqued interest because of their superior benefits over traditional techniques such as speed, sensitivity, directness and affordability. Subsequently, the purpose of this article is to show how to determine VFX electrochemically using a wide range of electrodes, including CPE, GCE, MCE, SPE, PGE and ISE.


Asunto(s)
Trastorno Depresivo Mayor , Nanoestructuras , Antidepresivos , Humanos , Fotólisis , Clorhidrato de Venlafaxina
13.
Environ Res ; 208: 112744, 2022 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-35065928

RESUMEN

Antibiotics might build up into the human body by foodstuff metabolism, posing a serious threat to human health and safety. Establishing simple and sensitive technology for quick antibiotic evaluation is thus extremely important. Nanomaterials (or NMTs) with the advantage of possessing merits such as remarkable optical, thermal, mechanical, and electrical capabilities have been highlighted as a piece of the best promising materials for rising new paths in the creation of the future generation biosensors. This paper presents the most recent advances in the use of graphene NMTs-based biosensors to determine antibiotics. Gr-NMTs (or graphene nanomaterials) have been used in the development of a biosensor for the electrochemical signal-transducing process. The rising issues and potential chances of this field are contained to give a plan for forthcoming research orientations. As a result, this review provides a comprehensive evaluation of the nanostructured electrochemical sensing approach for antibiotic residues in various systems. In this review, various electrochemical techniques such as CV, DPV, Stripping, EIS, LSV, chronoamperometry, SWV were employed to determine antibiotics. Additionally, this also demonstrates how graphene nanomaterials are employed to detect antibiotics.


Asunto(s)
Técnicas Biosensibles , Grafito , Nanoestructuras , Antibacterianos , Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Grafito/química , Humanos , Nanoestructuras/química
14.
Chemosphere ; 287(Pt 4): 132387, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34600004

RESUMEN

MXene-based nanomaterials (MBNs) are two-dimensional materials that exhibit a series of sought after properties, including rich surface chemistry, adjustable bandgap structures, high electrical conductivity, hydrophobicity, thermal stability, and large specific surface area. MBNs have an exemplar performance when applied for the degradation of hazardous pollutants with various advanced oxidation processes such as heterogeneous sonocatalysis. As such, this work focuses on the sonocatalytic degradation of various hazardous pollutants using MXene-based catalysts. First, the general principles of sonocatalysis are examined, followed by an analysis of the main components of the MXene-based sonocatalysts and their application for pollutant degradation. Lastly, ongoing challenges are highlighted with recommendations to address the issues.


Asunto(s)
Contaminantes Ambientales , Nanoestructuras , Catálisis , Conductividad Eléctrica
15.
Chemosphere ; 287(Pt 3): 132271, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34547560

RESUMEN

In this study, novel biogenic silver (AgNPs) and gold nanoparticles (AuNPs) were developed using a green approach with Ganoderma lucidum (GL) extract. The optimization of synthesis conditions for the best outcomes was conducted. The prepared materials were characterized and their applicability in catalysis, antibacterial and chemical sensing was comprehensively evaluated. The GL-AgNPs crystals were formed in a spherical shape with an average diameter of 50 nm, while GL-AuNPs exhibited multi-shaped structures with sizes ranging from 15 to 40 nm. As a catalyst, the synthesized nanoparticles showed excellent catalytic activity (>98% in 9 min) and reusability (>95% after five recycles) in converting 4-nitrophenol to 4-aminophenol. As an antimicrobial agent, GL-AuNPs were low effective in inhibiting the growth of bacteria, while GL-AgNPs expressed strong antibacterial activity against all the tested strains. The highest growth inhibition activity of GL-AgNPs was observed against B. subtilis (14.58 ± 0.35 mm), followed by B. cereus (13.8 ± 0.52 mm), P. aeruginosa (12.38 ± 0.64 mm), E. coli (11.3 ± 0.72 mm), and S. aureus (10.41 ± 0.31 mm). Besides, GL-AgNPs also demonstrated high selectivity and sensitivity in the colorimetric detection of Fe3+ in aqueous solution with a detection limit of 1.85 nM. Due to the suitable thickness of the protective organic layer and the appropriate particle size, GL-AgNPs validated the triple role as a high-performance catalyst, antimicrobial agent, and nanosensor for environmental monitoring and remediation.


Asunto(s)
Antiinfecciosos , Nanopartículas del Metal , Antibacterianos/farmacología , Catálisis , Colorimetría , Escherichia coli , Compuestos Férricos , Oro , Tecnología Química Verde , Iones , Pruebas de Sensibilidad Microbiana , Extractos Vegetales , Plata , Staphylococcus aureus
16.
Chemosphere ; 286(Pt 3): 131892, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34418663

RESUMEN

The research and technological advancements observed in the latest years in the nanotechnology field translated into significant application developments in various areas. This is particularly true for the renewable polymers area, where the nano-reinforcement of biobased materials leads to an increase in their technique and economic competitiveness. The efforts were predominantly focused on materials development and energy consumption minimization. However, attention must also be given to the widespread commercialization and the full characterization of any particular potential toxicological and environmental impact. Some of the most important nanomaterials used in recent years as fillers in the bioplastic industry are graphene-based materials (GBMs). GBMs have high surface area and biocompatibility and have interesting characterizations such as strangeness and flexibility. In this paper, the current state of the art for these GBMs in the bioplastics area, their challenges, and the strategies to overcome them are analyzed.


Asunto(s)
Grafito , Nanoestructuras , Nanotecnología , Polímeros
17.
Chemosphere ; 286(Pt 3): 131894, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34416589

RESUMEN

In this study, a simple and environment-friendly method has been successfully applied for the production of silver nanoparticles (AgNPs) using Poria cocos extract. The reaction time of 60 min, the temperature of 90 °C, and silver ion concentration of 2.0 mM were identified as the best condition for the PC-AgNPs fabrication. The XRD analysis confirmed a highly crystalline face-centered cubic structure of the biosynthesized material. The PC-AgNPs were presented separately in a spherical shape with an average crystal size of 20 nm, as endorsed by the TEM and FE-SEM measurements. The presence and crucial role of biomolecules in stabilizing the nanoparticles were elucidated by FTIR, EDX, and DLS techniques. The prepared biogenic nanoparticles were further applied for the reduction of 4-nitrophenol (4-NP) and colorimetric detection of Fe3+ ions. The study results proved that PC-AgNPs exhibited superior catalytic activity and reusability in the conversion of 4-NP by NaBH4. The complete reduction of 4-NP could be achieved in 10 min with the pseudo-first-order rate constant of 0.466 min-1, and no significant performance loss was found when the material was reused five times. The colorimetric probe based on PC-AgNPs displayed outstanding sensitivity and selectivity towards Fe3+ ions with a detection limit of 1.5 µM in a linear range of 0-250 µM. Additionally, the applicability of the developed assay was explored for testing Fe3+ ions in tap water. PC-AgNPs have a great potential for further applications as a promising catalyst for reducing nitrophenols and biosensors for the routine monitoring of Fe3+ in water.


Asunto(s)
Nanopartículas del Metal , Wolfiporia , Compuestos Férricos , Iones , Nitrofenoles , Extractos Vegetales , Plata
18.
J Hazard Mater ; 423(Pt A): 127016, 2022 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-34474364

RESUMEN

This study evaluates the degradation efficiency of Malathion using Fenton (Fe2+/H2O2: F), photo-Fenton (UV/Fe2+/H2O2: PF), and sono-photo Fenton (US/UV/Fe2+/H2O2: SPF) processes as well as determines the toxicity of the byproducts of degradation. The effect of various operational parameters on the Malathion degradation rate, including pH, Fe2+ concentration, Malathion concentration, and H2O2 were studied. The removal efficiency was determined to be 98.79% for the SPF, > 70.92% for the PF, and > 55.94% for the F processes under the following optimal conditions: pH = 3, [H2O2]0 = 700 mg/L, [Fe2+]0 = 20 mg/L, and [Malathion]0 = 20 mg/L. The operating costs (USD/kgMalathion-removed) were acquired as SPF > PF > F. Moreover, Malaoxon, diethyl maleate, diethyl malate, ethyl 2-hydroxysuccinate, and D-malate were among the detected byproducts from the Malathion degradation in the SPF process. Both the non-carcinogenic risk and the carcinogenic risk were assessed to establish the quality of the effluent from all three processes. The toxicity of the treated effluents, determined by Vibrio fischeri luminescence, indicated that the toxicity depends on the selected treatment process. The high degradation efficiency of the Fenton-based processes is not equivalent to achieving detoxification of the effluents. As such, the SPF process was determined to be the most effective for the Malathion degradation, total organic carbon (TOC) removal, and health risk assessment.


Asunto(s)
Plaguicidas , Contaminantes Químicos del Agua , Descontaminación , Peróxido de Hidrógeno/toxicidad , Hierro , Malatión/toxicidad , Oxidación-Reducción , Plaguicidas/toxicidad , Medición de Riesgo , Rayos Ultravioleta , Contaminantes Químicos del Agua/toxicidad
19.
Chemosphere ; 286(Pt 2): 131727, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34352554

RESUMEN

Due to its cytotoxic effect, metronidazole (MNZ) is a drug commonly used to treat bacterial, protozoal, and microaerophilic bacterial infections. After consumption, it undergoes a series of metamorphic reactions that lead to the degradation of oxidized, acetylated, and hydrolyzed metabolites in the environment. To eliminate such pollutants, due to their high potential, adsorption and photocatalysis extensive processes are used in which graphene can be used to improve efficiency. This review analyses the use of graphene as an absorbent and catalyst with a focus on absorption and photocatalytic degradation of MNZ by graphene-based materials (GBMs). The parameters affecting the adsorption, and photocatalytic degradation of MNZ are investigated and discussed. Besides, the basic mechanisms occurring in these processes are summarized and analyzed. This work provides a theoretical framework that can direct future research in the field of MNZ removal from aqueous solutions.


Asunto(s)
Grafito , Contaminantes Químicos del Agua , Adsorción , Catálisis , Metronidazol/análisis , Contaminantes Químicos del Agua/análisis
20.
Chemosphere ; 291(Pt 3): 133025, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34848226

RESUMEN

It is vital to have high sensitivity in gas sensors to allow the exact detection of dangerous gases in the air and at room temperature. In this study, we used 2D MXenes and MoS2 materials to create a Ti3C2-MoS2 composite with high metallic conductivity and a wholly functionalized surface for a significant signal. At room temperature, the Ti3C2-MoS2 composite demonstrated clear signals, cyclic response curves to NO2 gas, and gas concentration-dependent. The sensitivities of the standard Ti3C2-MoS2 (TM_2) composite (20 wt% MoS2) rose dramatically to 35.8%, 63.4%, and 72.5% when increasing NO2 concentrations to 10 ppm, 50 ppm, and 100 ppm, respectively. In addition, the composite showed reaction signals to additional hazardous gases, such as ammonia and methane. Our findings suggest that highly functionalized metallic sensing channels could be used to construct multigas-detecting sensors that are very sensitive in air and at room temperature.


Asunto(s)
Molibdeno , Titanio , Amoníaco , Gases , Molibdeno/toxicidad , Titanio/toxicidad
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