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1.
Small ; 20(35): e2401022, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38809081

RESUMO

Renewable energy technologies, such as water splitting, heavily depend on the oxygen evolution reaction (OER). Nanolaminated ternary compounds, referred to as MAX phases, show great promise for creating efficient electrocatalysts for OER. However, their limited intrinsic oxidative resistance hinders the utilization of conductivity in Mn+1Xn layers, leading to reduced activity. In this study, a method is proposed to improve the poor inoxidizability of MAX phases by carefully adjusting the elemental composition between Mn+1Xn layers and single-atom-thick A layers. The resulting Ta2FeC catalyst demonstrates superior performance compared to conventional Fe/C-based catalysts with a remarkable record-low overpotential of 247 mV (@10 mA cm-2) and sustained activity for over 240 h. Notably, during OER processing, the single-atom-thick Fe layer undergoes self-reconstruction and enrichment from the interior of the Ta2FeC MAX phase toward its surface, forming a Ta2FeC@Ta2C@FeOOH heterostructure. Through density functional theory (DFT) calculations, this study has found that the incorporation of Ta2FeC@Ta2C not only enhances the conductivity of FeOOH but also reduces the covalency of Fe─O bonds, thus alleviating the oxidation of Fe3+ and O2-. This implies that the Ta2FeC@Ta2C@FeOOH heterostructure experiences less lattice oxygen loss during the OER process compared to pure FeOOH, leading to significantly improved stability. These results highlight promising avenues for further exploration of MAX phases by strategically engineering M- and A-site engineering through multi-metal substitution, to develop M2AX@M2X@AOOH-based catalysts for oxygen evolution.

2.
Small ; 20(29): e2310576, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38402439

RESUMO

In search for novel materials to replace noble metal-based electrocatalysts in electrochemical energy conversion and storage devices, special attention is given to a distinct class of materials, MAX phase that combines advantages of ceramic and metallic properties. Herein, Nb4AlC3 MAX phase is prepared by a solid-state mixing reaction and characterized morphologically and structurally by transmission and scanning electron microscopy with energy-dispersive X-ray spectroscopy, nitrogen-sorption, X-ray diffraction analysis, X-ray photoelectron and Raman spectroscopy. Electrochemical performance of Nb4AlC3 in terms of capacitance as well as for oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) is evaluated in different electrolytes. The specific capacitance Cs of 66.4, 55.0, and 46.0 F g-1 at 5 mV s-1 is determined for acidic, neutral and alkaline medium, respectively. Continuous cycling reveals high capacitance retention in three electrolyte media; moreover, increase of capacitance is observed in acidic and neutral media. The electrochemical impedance spectroscopy showed a low charge transfer resistance of 64.76 Ω cm2 that resulted in better performance for HER in acidic medium (Tafel slope of 60 mV dec-1). In alkaline media, the charge storage value in the double layer is 360 mF cm-2 (0.7 V versus reversible hydrogen electrode) and the best ORR performance of the Nb4AlC3 is achieved in this medium (Tafel slope of 126 mV dec-1).

3.
Nanotechnology ; 35(38)2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38834036

RESUMO

MXenes have been attracting much attention since their introduction due to their amazing properties such as unique structure, good hydrophilicity, metal-grade electrical conductivity, rich surface chemistry, low ionic diffusion resistance, and excellent mechanical strength. It is noteworthy that different synthesis methods have a great influence on the structure and properties of MXenes. In recent years, some modification strategies of MXenes with unique insights have been developed with the increasing research. In summary, this paper reviews and summarizes the recent research progress of MXenes from the perspective of preparation processes (including hydrofluoric acid direct etching, fluoride/concentrated acid hybrid etching, fluoride melt etching, electrochemical etching, alkali-assisted etching and Lewis acid etching strategies), which can provide valuable guidance for the preparation and application of high-performance MXenes-based materials.

4.
Mikrochim Acta ; 191(3): 135, 2024 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-38355771

RESUMO

A highly sensitive electrochemical sensor is reported that employs a modified electrode for the precise measurement of cabotegravir, a potent anti-HIV drug. Cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS) were utilized for this purpose. Electrode modification involved the immobilization of Cr2AlC MAX phase/g-C3N4 onto a glassy carbon electrode (GCE) to enhance its electrocatalytic activity and selectivity for cabotegravir detection. Under the optimal experimental conditions, the working potential (vs. Ag/AgCl) was to 0.93 V. The developed sensor exhibited a good linear relationship in the range 0.05 µM to 9.34 µM with a low limit of detection of 4.33 nM, signifying its exceptional sensitivity. Additionally, it demonstrated successful cabotegravir detection in pharmaceutical formulations and biological samples, achieving an RSD below 3.0%. The recoveries fell within the range 97.7 to 102%, confirming the sensor's potential for real-sample applications. This innovative electrochemical sensor represents a significant advancement, providing a simple, reliable, and sensitive tool for the accurate measurement of cabotegravir. Its potential applications include optimizing drug dosages, monitoring treatment responses, and supporting the development of cabotegravir-based pharmaceutical products, thereby contributing to advancements in HIV therapy and prevention strategies.


Assuntos
Carbono , Dicetopiperazinas , Técnicas Eletroquímicas , Piridonas , Técnicas Eletroquímicas/métodos , Limite de Detecção , Carbono/química , Preparações Farmacêuticas
5.
Angew Chem Int Ed Engl ; 63(27): e202403508, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38647357

RESUMO

MXenes have extensive applications due to their different properties determined by intrinsic structures and various functional groups. Exploring different functional groups of MXenes leads to improved performance or potential applications. In this work, we prepared new Ti3C2PBrx (x=0.4-0.6) MXene with phosphorus functional groups (-P) through a two-step gas-phase reaction. The acquisition of -P is achieved by replacing bromine functional groups (-Br) of Ti3C2Br2 in the phosphorus vapor. After -Br is replaced with -P, Ti3C2PBrx MXene shows an improved areal capacitance (360 mF cm-2) at 20 mV s-1 compared with Ti3C2Br2 MXene (102 mF cm-2). At a current density of 5 mA cm-2 after 10000 cycles, the capacitance retention of Ti3C2PBrx MXene has not decreased. The pseudocapacitive enhancement mechanism has been discovered based on the dual redox sites of the functional groups -P and Ti.

6.
Small ; 19(27): e2300119, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36974601

RESUMO

Microstructures play a critical role to influence the polarization behavior of dielectric materials, which determines the electromagnetic response ability in gigahertz. However, the relationship between them, especially in the solid-solution structures is still absent. Herein, a series of (Ti1- y Nby )2 AlC MAX phase solid solutions with nano-laminated structures have been employed to illuminate the aforementioned problem. The relationship has been investigated by the lattice distortion constructed via tuning the composition from Ti to Nb in the M-site atomic layer. Experimental characterizations indicated that the dielectric response behaviors between declined conduction loss and boosted polarization loss can be well balanced by niobium atom manipulative solid-solution engineering, which is conducive to impedance matching and electromagnetic absorption performance. Theoretical calculation further proved that the origin of electric dipoles is ascribed to the charge density differences resulting from the altered microscopic atomic distribution. As a result, the Ti1.2 Nb0.8 AlC exhibits the mostly optimized microwave absorption property, in which a minimum reflection loss of -42 dB and an effective absorption bandwidth of 4.3 GHz under an ultra-thin thickness of 1.4 mm can be obtained. This work provides insight into the structural engineering in modifying electromagnetic response performance at gigahertz and which can be expanded to other solid-solution materials.

7.
Diam Relat Mater ; 131: 109557, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36415485

RESUMO

The long-running Covid-19 pandemic has forced researchers across the globe to develop novel sensors and sensor materials for detecting minute quantities of biogenic viruses with high accuracy in a short period. In this context, MXene galleries comprising carbon/nitride two-dimensional nanolayered materials have emerged as excellent host materials in chemical gas sensors owing to their multiple advantages, including high surface area, high electrical conductivity, good thermal/chemical conductivity and chemical stability, composition diversity, and layer-spacing tunability; furthermore, they are popular in clinical, medical, food production, and chemical industries. This review summarizes recent advances in the synthesis, structure, and gas-sensing properties of MXene materials. Current opportunities and future challenges for obtaining MXene-based chemical gas sensors with high sensitivity, selectivity, response/recovery time, and chemical durability are addressed. This review provides a rational and in-depth understanding of the relationship between the gas-sensing properties of MXenes and structure/components, which will promote the further development of two-dimensional MXene-based gas sensors for technical device fabrication and industrial processing applications.

8.
Environ Res ; 212(Pt A): 113071, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35346651

RESUMO

Bisphenol A (BPA) is an industrially preferred material for the production of plastic and polycarbonate as well as a used material for the interior of food and beverage cans. In this study, synthesis and electrochemical sensor application of Mo2Ti2AlC3/MWCNT (multi-walled carbon nanotube) nanocomposite for BPA sensing was evaluated. Mo2Ti2AlC3 was used as MAX phase material in the design of the sensor, and MWCNT was preferred to increase conductivity and sensitivity. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were used to determine Mo2Ti2AlC3/MWCNT nanocomposite's electrochemical sensor performances which had LOD of 2.7 nM and LOQ of 8.91 nM in the linear working range of 0.01-8.50 µM calculated from DPV. The composite showed a single oxidation step against BPA which is diffusion-controlled and irreversible. The sensor was successfully applied for the determination of BPA in milk pack, plastic bottle, and can with recoveries ranging from 95.67% to 100.60%. In addition, sensor performance was examined through selectivity, repeatability, and reusability studies. HPLC as a standard determination method was carried out for accuracy of the voltammetric determination method in the real samples. The developed sensor could be applied to different areas from industry quality control to clinical analysis for the detection of BPA.


Assuntos
Disruptores Endócrinos , Nanotubos de Carbono , Compostos Benzidrílicos , Técnicas Eletroquímicas/métodos , Eletrodos , Disruptores Endócrinos/análise , Limite de Detecção , Fenóis , Plásticos , Titânio
9.
Molecules ; 27(24)2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36558045

RESUMO

In this research work, the Ti2SnC MAX phase (MP) was synthesized via the reactive sintering procedure. The layered and crystalline structure of this MP was verified by SEM, HRTEM, and XRD analyses. This nano-additive was used for improvement of different features of the polyethersulfone (PES) polymeric membranes. The blended membranes containing diverse quantities of the MP (0-1 wt%) were fabricated by a non-solvent-induced phase inversion method. The asymmetric structure of the membranes with small holes in the top layer and coarse finger-like holes and macro-voids in the sublayer was observed by applying SEM analysis. The improvement of the membrane's hydrophilicity was verified via reducing the contact angle of the membranes from 63.38° to 49.77° (for bare and optimum membranes, respectively). Additionally, in the presence of 0.5 wt% MP, the pure water flux increased from 286 h to 355 L/m2 h. The average roughness of this membrane increased in comparison with the bare membrane, which shows the increase in the filtration-available area. The high separation efficiency of the oil/water emulsion (80%) with an improved flux recovery ratio of 65% was illustrated by the optimum blended membrane.


Assuntos
Incrustação Biológica , Incrustação Biológica/prevenção & controle , Membranas Artificiais , Titânio , Interações Hidrofóbicas e Hidrofílicas
10.
Mikrochim Acta ; 187(2): 151, 2020 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-31997010

RESUMO

Two dimensional accordion-like Ti3C2Tx MXene, where Tx represents surface termination groups such as -OH, -O-, and -F, is synthesized by selective etching of aluminum layers from Ti3AlC2. This manuscript reports on the adsorption of organic molecules from head-space and aqueous environments containing Ti3C2Tx, a representative of the MXene family. Ti3C2Tx coated by gluing method on a stainless steel wire was successfully utilized as a highly sensitive and stable head-space solid-phase microextraction (SPME) fiber. A SPME method with the MXene as the adsorbent combined with gas chromatography with MS detector was used to determine the polycyclic aromatic hydrocarbons (PAHs) in water samples. Low detection limits in the range of 0.2-5 ng L-1, wide linearity and good reproducibility (RSD = 4.6 to 7.4% for n = 6) under the optimized extraction conditions was achieved. Finally, the MXene coated fiber was successfully used for the determination of PAHs in real water samples. The relative recoveries for six PAHs are from 91.3-105.0%, which proved the applicability of the method. Also, melamine was selected as a polar analyte and it has been shown that Ti3C2Tx MXene has good capability in extraction of melamine (the extraction recovery for melamine = 80.1%) from aqueous media by dispersive micro solid-phase extraction. Graphical abstractTwo dimensional accordion-like Ti3C2 MXene was synthesized by selective etching of aluminum layers from Ti3AlC2. Ti3C2 MXene was employed as solid phase microextraction fiber coating for the extraction of polycyclic aromatic hydrocarbons from water samples.

11.
Angew Chem Int Ed Engl ; 54(16): 4810-4, 2015 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-25714491

RESUMO

Herein we electrochemically and selectively extract Ti from the MAX phase Ti2SC to form carbon/sulfur (C/S) nanolaminates at room temperature. The products are composed of multi-layers of C/S flakes, with predominantly amorphous and some graphene-like structures. Covalent bonding between C and S is observed in the nanolaminates, which render the latter promising candidates as electrode materials for Li-S batteries. We also show that it is possible to extract Ti from other MAX phases, such as Ti3AlC2, Ti3SnC2, and Ti2GeC, suggesting that electrochemical etching can be a powerful method to selectively extract the "M" elements from the MAX phases, to produce "AX" layered structures, that cannot be made otherwise. The latter hold promise for a variety of applications, such as energy storage, catalysis, etc.

12.
Sci Technol Adv Mater ; 15(1): 014208, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27877635

RESUMO

The experimental exfoliation of layered, ternary transition-metal carbide and nitride compounds, known as MAX phases, into two-dimensional (2D) nanosheets, is a great development in the synthesis of novel low-dimensional inorganic systems. Among the MAX phases, Mo-containing ones might be considered as the source for obtaining Mo2C nanosheets with potentially unique properties, if they could be exfoliated. Here, by using a set of first-principles calculations, we discuss the effect of the interlayer 'A' element on the exfoliation of Mo2AC (A = Al, Si, P, Ga, Ge, As or In) MAX phases into the 2D Mo2C nanosheets. Based on the calculated exfoliation energies and the elastic constants, we propose that Mo2InC with the lowest exfoliation energy and the highest elastic constant anisotropy between C11 and C33 might be a suitable compound for exfoliation into 2D Mo2C nanosheets.

13.
Sci Rep ; 14(1): 17516, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39080294

RESUMO

Nb 2 SC and Nb 2 AsC are among the identified superconducting MAX phases, both exhibiting a transition temperature T c lower than 10 K. These compounds appear to belong to the conventional class of superconductors. By calculating the electron-phonon couplings of these materials, we have found that the predicted transition temperatures are approximately 6 K for Nb 2 SC and 2 K for Nb 2 AsC, closely matching the experimental findings. However, when subjected to pressure or strain, Nb 2 SC and Nb 2 AsC exhibit contrasting behaviors. While the transition temperature of Nb 2 SC can be doubled by applying pressure up to 50 GPa, the transition temperature of Nb 2 AsC significantly decreases under the same pressure. On the other hand, in the case of Nb 2 AsC, a uniaxial tensile strain of approximately 2% along the c direction can enhance the compound's transition temperature by about 40%. These results show that with the right pressure or strain, it is possible to increase superconducting transition temperature in the Nb 2 AC compounds.

14.
Sci Total Environ ; 929: 172189, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38583624

RESUMO

This study explores the incorporation of Nb2AlC and Mo3AlC2 MAX phases, known for their nano-layered structure, into polyether sulfone (PES) membranes to enhance their antifouling and permeability properties for pathogen microorganism filtration against bovine serum albumin (BSA) and Escherichia coli (E. coli). The composite membranes were characterized for their structural and morphological properties, and their performance in mitigating biofouling was evaluated. The structural characterizations have been performed for all the prepared MAX phases and corresponding composite membranes. The antioxidant ability of Nb2AlC and Mo3AlC2 MAX phases was defined by the DPPH radical scavenging assay, and the highest antioxidant ability was found to be 59.35 %, while 53.69 % scavenging potential was recorded at 100 mg/L. The percentage scavenging ability was raised with an increase in concentrations. The antimicrobial properties of MAX phases, evaluated as the minimum inhibitory concentration, were stated against several pathogen microorganisms. The tested compounds of Nb2AlC and Mo3AlC2 composites containing MAX phases exhibited excellent chemical nuclease activity, and it was determined that Nb2AlC caused double strand DNA cleavage activity while Mo3AlC2 induced the complete fragmentation of the DNA molecule. Biofilm inhibition of Nb2AlC and Mo3AlC2 MAX phases was studied against Staphylococcus aureus, and Pseudomonas aeruginosa and the maximum biofilm inhibition of Nb2AlC and Mo3AlC2 MAX phases was found to be 77.15 % and 69.07 % against S. aureus and also 69.74 % and 65.01 % against P. aeruginosa. Furthermore, Nb2AlC and Mo3AlC2 MAX phases demonstrated excellent E. coli growth inhibition of 100 % at 125 and 250 mg/L.


Assuntos
Incrustação Biológica , Escherichia coli , Membranas Artificiais , Polímeros , Sulfonas , Incrustação Biológica/prevenção & controle , Sulfonas/farmacologia , Sulfonas/química , Polímeros/farmacologia , Escherichia coli/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Filtração
15.
Chemosphere ; 362: 142583, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38866342

RESUMO

In this work, the hydrophobic polyethersulfone (PES) membrane was modified by incorporating Ti3AlCN MAX phase. Synthesis of Ti3AlCN MAX phase was performed using the reactive sintering method. The scanning electron microscopy (SEM) images showed a 3D compressed layered morphology for the synthesized MAX phase. The Ti3AlCN MAX phase was added to the casting solution, and the mixed-matrix membranes were fabricated by the non-solvent induced phase inversion method. The performance and antifouling features of bare and modified membranes were explored by pure water flux, flux recovery ratio (FRR), and fouling resistance parameters. Through the modification of membranes by introducing the Ti3AlCN MAX phase, the enhancement of these features was observed, in which the membrane containing 1 wt% of MAX phase showed 17.7 L/m2.h.bar of permeability and 98.6% for FRR. Also, the separation efficiency of all membranes was evaluated by rejecting organic and inorganic pollutants. The Ti3AlCN MAX membranes could reject 96%, 95%, and 88% of reactive blue 50, Rose Bengal, and azithromycin antibiotics, respectively, as well as 98%, 80%, 86%, and 36% of Pb2+, As5+, Na2SO4, and NaCl, respectively. Finally, the outcomes indicated the Ti3AlCN MAX phase was an excellent and efficient novel additive for modifying the PES membrane.


Assuntos
Membranas Artificiais , Polímeros , Sulfonas , Titânio , Poluentes Químicos da Água , Sulfonas/química , Polímeros/química , Titânio/química , Poluentes Químicos da Água/química , Interações Hidrofóbicas e Hidrofílicas , Permeabilidade , Purificação da Água/métodos
16.
Nanomaterials (Basel) ; 14(7)2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38607150

RESUMO

Broad adoption has already been started of MXene materials in various energy storage technologies, such as super-capacitors and batteries, due to the increasing versatility of the preparation methods, as well as the ongoing discovery of new members. The essential requirements for an excellent anode material for lithium-ion batteries (LIBs) are high safety, minimal volume expansion during the lithiation/de-lithiation process, high cyclic stability, and high Li+ storage capability. However, most of the anode materials for LIBs, such as graphite, SnO2, Si, Al, and Li4Ti5O12, have at least one issue. Hence, creating novel anode materials continues to be difficult. To date, a few MXenes have been investigated experimentally as anodes of LIBs due to their distinct active voltage windows, large power capabilities, and longer cyclic life. The objective of this review paper is to provide an overview of the synthesis and characterization characteristics of the MXenes as anode materials of LIBs, including their discharge/charge capacity, rate performance, and cycle ability. In addition, a summary of the potential outlook for developments of these materials as anodes is provided.

17.
Int J Biol Macromol ; 270(Pt 2): 132380, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38754656

RESUMO

Clean water and sanitation issues motivate researchers to develop water evaporators for freshwater generation. The composite membrane evaporator was electrospun herein based on poly(lactic acid) (PLA) and Ti3AlC2 MAX phase as a property enhancer. As a precursor for the MXenes synthesis, the MAX phase has never been explored with PLA for water evaporator potential. Alternative use of the MAX phase can reduce the production cost arising from chemical synthesis. This work explored the potential of the MAX phase as an additive to enhance PLA membrane performance for steam generation and desalination applications. Under the infrared irradiation (∼1.0 kW/m2), the mechanically-improved PLA/MAX phase membrane showed an enhanced water evaporation rate of 1.70 kg/m2 h (93.93 % efficiency), with an approximately 52 % rate increment relative to the PLA membrane. Based on the artificial seawater (3.5 % w/w), the membrane exhibited an evaporation rate of 1.60 kg/m2 h (87.57 % efficiency). The membrane showed self-floating ability at the air-water interface, excellent thermal stability over the entire operating temperatures, and reusability after repeated cycles. Moreover, the generated freshwater contained exceptionally low cations concentrations, as low as those in potable water. The developed composite membrane also had proved its potential for solar desalination in the water generation field.


Assuntos
Membranas Artificiais , Poliésteres , Vapor , Titânio , Purificação da Água , Poliésteres/química , Titânio/química , Purificação da Água/métodos , Luz Solar
18.
Front Chem ; 12: 1413253, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39021388

RESUMO

MAX phases, characterized as nanolaminates of ternary carbides/nitrides structure, possess a unique combination of ceramic and metallic properties, rendering them pivotal in materials research. In this study, chromium aluminum carbide ternary compounds, Cr2AlC (211), Cr3AlC2 (312), and Cr4AlC3 (413) were successfully synthesized with high purity using a facile and cost-effective sol-gel method. Structural, morphological, and chemical characterization of the synthesized phases was conducted to understand the effects of composition changes and explore potential applications. Comprehensive characterization techniques including XRD for crystalline structure elucidations, SEM for morphological analysis, EDX for chemical composition, Raman spectroscopy for elucidation of vibrational modes, XPS to analyze elemental composition and surface chemistry, and FTIR spectroscopy to ensure the functional groups analysis, were performed. X-ray diffraction analysis indicated the high purity of the synthesized Cr2AlC phase as well as other ternary compounds Cr3AlC2 and Cr4AlC3, suggesting its suitability as a precursor for MXenes production. Additionally, the antimicrobial activity against Candida albicans and biocompatibility assessments against Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), and HepG2 cell line were investigated. The results demonstrated significant antifungal activity of the synthesized phases against Candida albicans and negligible impact on the viability of E. coli and S. aureus. Interestingly, lower concentrations of Cr2AlC MAX phase induced cytotoxicity in HepG2 cells by triggering intercellular oxidative stress, while Cr3AlC2 and Cr4AlC3 exhibited lower cytotoxicity compared to Cr2AlC, highlighting their potential in biomedical applications.

19.
Int J Biol Macromol ; 262(Pt 1): 129967, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38316324

RESUMO

MXenes, synthesized from their precursor MAX phases, have been extensively researched as additives to enhance the drug delivery performance of polymer matrices, whereas there is a limited number of previous reports on the use of MAX phases themselves for such applications. The use of MAX phases can exclude the complicated synthesis procedure and lessen resultant production and environmental costs required to convert MAX phases to MXenes. Herein, electrospun membranes of poly(lactic acid) (PLA) and a MAX phase (Ti3AlC2) have been fabricated for curcumin delivery. The composite membrane exhibits significantly higher toughness (8.82 MJ m-3) than the plasticized PLA membrane (0.63 MJ m-3) with low cytotoxicity, supporting proliferation of mouse fibroblast L929 cells. The curcumin-loaded composite membrane exhibits high water vapor transmission (∼7350 g m-2 day-1), porosity (∼85 %), water wettability, and antibacterial properties against E. coli and S. aureus. Seven-day curcumin release is enhanced from 45 % (PLA) to 67 % (composite) due to curcumin diffusion from the polymer fibers and MAX phase surface that contributes to overall increased curcumin adsorption and release sites. This work demonstrates the potential of the MAX phase to enhance both properties and curcumin delivery, promising for other eco-friendly systems for sustainable drug delivery applications.


Assuntos
Curcumina , Animais , Camundongos , Curcumina/farmacologia , Staphylococcus aureus , Escherichia coli , Titânio , Poliésteres , Antibacterianos/farmacologia , Polímeros
20.
Micromachines (Basel) ; 15(5)2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38793207

RESUMO

Hydrazine is considered a powerful reducing agent and catalyst, showing diverse applications in agricultural industries, toxic degradation research, and wastewater management. Additionally, hydrazine can trigger some specific reactions when combined with suitable oxidants. Due to its highly polar nature, hydrazine can easily dissolve in alcohol, water, and various other polar solvents. Therefore, it can be extensively utilized in different areas of application and industries such as rocketry and various chemical applications. Despite its beneficial properties, hydrazine is unstable, posing significant risk due to its highly toxic nature. It is extremely hazardous to both human health and the environment. It can cause various illnesses and symptoms such as dizziness, temporary blindness, damage to the central nervous system, and even death when inhaled in sufficient quantities. Therefore, it is highly important to monitor the level of hydrazine to prevent its toxic and hazardous effects on human beings and the environment. In the present study, we discuss the simple fabrication of a disposable cost-effective and eco-friendly hydrazine sensor. We used a screen-printed carbon electrode, i.e., SPCE, as a base for the construction of a hydrazine sensor. The Ti3AlC2 MAX has been used as a suitable and efficient electrode material for the fabrication of disposable hydrazine sensors. We modified the active surface of the SPCE using a drop-casting approach. The resulting Ti3AlC2 MAX modified SPCE (Ti3AlC2@SPCE) has been utilized as an efficient and low-cost hydrazine sensor. Cyclic voltammetry, i.e., CV, and linear sweep voltammetry, viz., LSV, was employed as a sensing technique in this study. The optimization of pH and electrode material loading was conducted. The Ti3AlC2@SPCE exhibited excellent sensing performance toward hydrazine oxidation. A reasonable detection limit (0.01 µM) was achieved for hydrazine sensing. The fabricated sensor also demonstrated a reasonable linear range of 1-50 µM. This work provides the design and fabrication of simple disposable Ti3AlC2@SPCE as a suitable electrode for the determination of hydrazine using LSV technology.

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