Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 56
Filtrar
1.
Small ; : e2310112, 2024 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-38221688

RESUMO

The development of effective oxygen evolution reaction (OER) and urea oxidation reaction (UOR) on heterostructure electrocatalysts with specific interfaces and characteristics provides a distinctive character. In this study, heterostructure nanocubes (NCs) comprising inner cobalt oxysulfide (CoOS) NCs and outer CoFe (CF) layered double hydroxide (LDH) are developed using a hydrothermal methodology. During the sulfidation process, the divalent sulfur ions (S2- ) are released from the breakdown of the sulfur source and react with the Co-precursors on the surface leading to the transformation of CoOH nanorods into CoOS nanocubes. Further, X-ray photoelectron spectroscopy (XPS) and X-ray absorption spectroscopy (XAS) analyses reveal that the interactions at the interface of the CF@CoOS NCs significantly altered the electronic structure, thus enhancing the electrocatalytic performance. The optimal catalysts exhibited effective OER and UOR activities, the attained potentials are 1.51 and 1.36 V. This remarkable performance is attributable to the induction of electron transfer from the CoFe LDH to CoOS, which reduces the energy barrier of the intermediates for the OER and UOR. Furthermore, an alkaline water and urea two-cell electrolyzer assembled using CF@CoOS-2 NCs and Pt/C as the anode and cathode requires a cell voltage of 1.63 and 1.56 V along with a durability performance.

2.
Int J Mol Sci ; 24(22)2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38003475

RESUMO

A key challenge in the development of sustainable water-splitting (WS) systems is the formulation of electrodes by efficient combinations of electrocatalyst and binder materials. Cellulose, a biopolymer, can be considered an excellent dispersing agent and binder that can replace high-cost synthetic polymers to construct low-cost electrodes. Herein, a novel electrocatalyst was fabricated by combining Fe2O3 and Ni on microcrystalline cellulose (MCC) without the use of any additional binder. Structural characterization techniques confirmed the formation of the Fe2O3-Ni nanocomposite. Microstructural studies confirmed the homogeneity of the ~50 nm-sized Fe2O3-Ni on MCC. The WS performance, which involves the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER), was evaluated using a 1 M KOH electrolyte solution. The Fe2O3-Ni nanocomposite on MCC displayed an efficient performance toward lowering the overpotential in both the HER (163 mV @ 10 mA cm-2) and OER (360 mV @ 10 mA cm-2). These results demonstrate that MCC facilitated the cohesive binding of electrocatalyst materials and attachment to the substrate surface. In the future, modified cellulose-based structures (such as functionalized gels and those dissolved in various media) can be used as efficient binder materials and alternative options for preparing electrodes for WS applications.


Assuntos
Celulose , Nanocompostos , Polímeros , Hidrogênio , Oxigênio , Água
3.
Heliyon ; 9(10): e20824, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37867874

RESUMO

Photocatalysts workable under direct sunlight are the safe and cost-effective option for water purification. The nanocomposites of strontium oxide and zinc oxide (SZ NCs) were synthesized using coprecipitation method. The respective precursors of SZ NCs were subjected to alkaline hydrolysis and subsequently thermally treated to yield SZ NCs. The SZ NCs with different ZnO composition was synthesized by varying the concentration of ZnO precursor from 0.2 to 1 M. The structural properties of SZ NCs evaluated using X-Ray diffraction (XRD), Thermogravimetric analysis (TGA), and Differential thermal analysis DTA). The optical properties of SZ NCs studied using ultraviolet-visible (UV-Vis) spectroscopic study. The trend observed in the intensity of XRD peaks indicated the occurrence of Zn doping in the crystalline lattice of SrO and the formation of SrO-ZnO composite. Upon incorporation of 1 M of ZnO precursor, the grain size of the SrO was decreased from 49.3 to 27.6 nm. The weight loss in the thermal analysis indicates the removal of carbonates from the sample upon heating and shows the formation of an oxide structure. UV-Vis spectra confirmed that the presence of SrO enhanced the sunlight absorption of SZ NCs. The increase in the composition of ZnO precursors increased the bandgap of SrO (2.09 eV) to the level of ZnO (3.14 eV). SZ NCs exhibited heterostructure morphology, where the nanosized domains with varying shapes (layered and rod-like) were observed. Under direct sunlight conditions, SZ NCs prepared using 1 M/0.6 M of SrO/ZnO precursors exhibited 15-20 % higher photocatalytic efficiency than neat SrO and ZnO. In precise, 1 mg of this SZ NC was degraded 98 % of malachite green dye dissolved in water (10 ppm) under direct sunlight. Additionally, the thermal stability results showed that 18 % decomposition was obtained due to the degradation impurities in SrO/ZnO catalysts and the XRD results revealed that no structural change is obtained in SrO/ZnO photocatalysts after stability test. The SZ NCs can be effectively used as safe and economic sunlight photocatalysts for water purification in remote areas without the electricity.

4.
Plants (Basel) ; 12(20)2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37896010

RESUMO

Centella asiatica (CA) is a medicinal plant widely used in the East, with many of its phytoconstituents remaining unexplored. In this study, compounds were extracted and identified from C. asiatica to determine its medicinal properties. Phytochemical screening was conducted on shoot, callus, and cell suspension extracts, revealing the presence of tannins, flavonoids, terpenoids, saponins, and steroids in all three cultures, with no alkaloids detected. IC50 values were determined to evaluate the antioxidant activity of the extracts, with the highest value observed for cell suspension culture (20 µg/mL), followed by shoot culture (19 µg/mL), and then callus extract (10 µg/mL), with ascorbic acid as the standard at an IC50 value of 26.25 µg/mL. Finally, density functional theory was used to analyze the structure-activity relationships of the identified compounds from C. asiatica extract. The results suggest that ultrasonic-assisted extraction yielded the highest recovery and antioxidant activity, with a scavenging activity of 79%. This study provides valuable insights into the phytochemical composition and antioxidant potential of C. asiatica, which may have implications for its use in traditional medicine and future drug development.

5.
Int J Biol Macromol ; 253(Pt 7): 127471, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37863142

RESUMO

As an excellent alternative to petroleum-based food packaging materials, a novel green hybrid composite film with an excellent interconnected network structure was successfully fabricated by integrating chitosan (chi), microcrystalline cellulose (MCC), and lignin nanoparticles (LNP), including the desired amount of plasticizer glycerol (gly). Overall, 36 combinations were developed and investigated for superior biocomposite film formation. Among the various concentration ratios, the 40:35:25 chi-MCC-gly film provided well-organized film formation, good physicochemical properties, mechanical stability, efficient water contact angle, reduced water solubility, and lower water vapor permeability (11.43 ± 0.55 × 10-11 g.m-1.s-1.Pa-1). The performance of the chi-MCC-gly film further enhanced by the homogeneous incorporation of ∼100 nm LNP. With 1 % LNP addition, the tensile strength of the film increased (28.09 MPa, 47.10 % increase) and the water vapor permeability reached a minimum of 11.43 × 10-11 g.m-1.s-1.Pa-1, which proved the impact of LNP in composite films. Moreover, the films showed excellent resistance to thermal shrinkage even at 100 °C and exhibited nearly 100 % UV blocking efficiency at higher LNP concentrations. Interestingly, the green composite films extended the shelf life of freshly cut cherry tomatoes to seven days without spoilage. Overall, the facile synthesis of strong, insoluble, UV-blocking, and thermally stable green composite films realized for food packaging applications.


Assuntos
Quitosana , Lignina , Quitosana/química , Vapor , Biopolímeros/química , Embalagem de Alimentos
6.
Materials (Basel) ; 16(17)2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37687493

RESUMO

In this study, novel V2O5-decorated garlic peel biochar (VO/GPB) nanocomposites are prepared via the facile hydrothermal technique. As-synthesized VO/GPB is characterized by various spectroscopic and analytical techniques. The surface morphology of the as-prepared samples was predicted by SEM analysis, which shows that the block-like V2O5 was uniformly decorated on the stone-like GPB surface. The elemental mapping analysis confirms the VO/GPB composite is composed of the following elements: C, O, Na, Mg, Si, P, K, and V, without any other impurities. The photocatalytic activity of the VO/GPB nanocomposite was examined by the degradation of methyl orange (MO) under the irradiation of visible light; 84% degradation efficiency was achieved within 30 min. The reactive oxidative species (ROS) study reveals that hydroxyl and superoxide radicals play an essential role in MO degradation. Moreover, the antioxidant action of the VO/GPB nanocomposite was also investigated. From the results, the VO/GPB composite has higher antioxidant activity compared to ascorbic acid; the scavenging effect increased with increasing concentrations of VO/GPB composite until it reached 40 mg/L, where the scavenging effect was the highest at 93.86%. This study will afford innovative insights into other photocatalytic nanomaterials with effective applications in the field of photocatalytic studies with environmental compensation.

7.
Membranes (Basel) ; 13(9)2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37755180

RESUMO

Chitosan (CS), a promising potential biopolymer with exquisite biocompatibility, economic viability, hydrophilicity, and chemical modifications, has drawn interest as an alternative material for proton exchange membrane (PEM) fabrication. However, CS in its original form exhibited low proton conductivity and mechanical stability, restricting its usage in PEM development. In this work, chitosan was functionalized (sulfonic acid (-SO3H) groups)) to enhance proton conductivity. The sulfonated chitosan (sCS) was blended with polyvinylidene fluoride (PVDF) polymer, along with the incorporation of functionalized SiO2 (-OH groups), for fabricating chitosan-based composite proton exchange membranes to enhance microbial fuel cell (MFC) performances. The results show that adding functionalized inorganic fillers (fSiO2) into the membrane enhances the mechanical, thermal, and anti-biofouling behavior. From the results, the PVDF/sCS/fSiO2 composite membrane exhibited enhanced proton conductivity 1.0644 × 10-2 S cm-1 at room temperature and increased IEC and mechanical and chemical stability. Furthermore, this study presents a revolutionary way to generate environmentally friendly natural polymer-based membrane materials for developing PEM candidates for enhanced MFC performances in generating bioelectricity and wastewater treatment.

8.
Database (Oxford) ; 20232023 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-37702993

RESUMO

The present article describes the building of a small-molecule web server, CBPDdb, employing R-shiny. For the generation of the web server, three compounds were chosen, namely coumarin, benzothiazole and pyrazole, and their derivatives were curated from the literature. The two-dimensional (2D) structures were drawn using ChemDraw, and the .sdf file was created employing Discovery Studio Visualizer v2017. These compounds were read on the R-shiny app using ChemmineR, and the dataframe consisting of a total of 1146 compounds was generated and manipulated employing the dplyr package. The web server is provided with JSME 2D sketcher. The descriptors of the compounds are obtained using propOB with a filter. The users can download the filtered data in the .csv and .sdf formats, and the entire dataset of a compound can be downloaded in .sdf format. This web server facilitates the researchers to screen plausible inhibitors for different diseases. Additionally, the method used in building the web server can be adapted for developing other small-molecule databases (web servers) in RStudio. Database URL: https://srampogu.shinyapps.io/CBPDdb_Revised/.


Assuntos
Benzotiazóis , Cumarínicos , Bases de Dados Factuais , Pirazóis
9.
Polymers (Basel) ; 15(16)2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37631514

RESUMO

Customer demand for natural packaging materials in the food industry has increased. Biocomposite films developed using boiled rice water could be an eco-friendly and cost-effective packaging product in the future. This study reports the development of bio-based films using waste materials, such as boiled rice water (matrix) and Pistacia vera shells (reinforcement material), using an adapted solution casting method. Several film combinations were developed using various concentrations of plasticizing agent (sorbitol), thickening agent (oil and agar), and stabilizing agents (Arabic gum, corn starch, and Pistacia vera shell powder). Various packaging properties of the film were analyzed and examined to select the best bio-based film for food packaging applications. The film fabricated with Pistacia vera shell powder in the biocomposite film exhibited a reduced water solubility, swelling index, and moisture content, as compared to polyethene packaging material, whereas the biocomposite film exhibited poor antimicrobial properties, high vapor transmission rate, and high biodegradability rate. The packaging properties and characterization of the film indicated that the boiled rice water film with Pistacia vera shell powder was suitable for packaging material applications.

10.
Biomimetics (Basel) ; 8(4)2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37622935

RESUMO

Selective laser sintering (SLS) is an additive manufacturing process that has shown promise in the production of medical devices, including hip cups, knee trays, dental crowns, and hearing aids. SLS-based 3D-printed dosage forms have the potential to revolutionise the production of personalised drugs. The ability to manipulate the porosity of printed materials is a particularly exciting aspect of SLS. Porous tablet formulations produced by SLS can disintegrate orally within seconds, which is challenging to achieve with traditional methods. SLS also enables the creation of amorphous solid dispersions in a single step, rather than the multi-step process required with conventional methods. This review provides an overview of 3D printing, describes the operating mechanism and necessary materials for SLS, and highlights recent advances in SLS for biomedical and pharmaceutical applications. Furthermore, an in-depth comparison and contrast of various 3D printing technologies for their effectiveness in tissue engineering applications is also presented in this review.

11.
J Funct Biomater ; 14(8)2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37623670

RESUMO

Nanomaterials (NMs) synthesized from natural sources have been attracting greater attention, due to their intrinsic advantages including biocompatibility, stimuli-responsive property, nontoxicity, cost-effectiveness, and non-immunogenic characteristics in the biological environment. Among various biomedical applications, a breakthrough has been achieved in the development of drug delivery systems (DDS). Biocompatibility is necessary for treating a disease safely without any adverse effects. Some components in DDS respond to the physiological environment, such as pH, temperature, and functional group at the target, which facilitates targeted drug release. NM-based DDS is being applied for treating cancer, arthritis, cardiovascular diseases, and dermal and ophthalmic diseases. Metal nanomaterials and carbon quantum dots are synthesized and stabilized using functional molecules extracted from natural sources. Polymers, mucilage and gums, exosomes, and molecules with biological activities are directly derived from natural sources. In DDS, these functional components have been used as drug carriers, imaging agents, targeting moieties, and super disintegrants. Plant extracts, biowaste, biomass, and microorganisms have been used as the natural source for obtaining these NMs. This review highlights the natural sources, synthesis, and application of metallic materials, polymeric materials, carbon dots, mucilage and gums, and exosomes in DDS. Aside from that, challenges and future perspectives on using natural resources for DDS are also discussed.

12.
Int J Biol Macromol ; 252: 126205, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37562471

RESUMO

The use of marine waste derived chitosan (CS) for the synthesis of nanomaterials is considered as one of the effective routes for bio-waste management and recovering functional products. Herein, CS capped silver nanoparticles (Ag NPs-CS) with potential anticancer and dye pollutants adoption properties have been synthesized photochemically under direct sunlight. To obtain, CS, shrimp shell waste was subjected to a serious of standard demineralization, deproteinization and deacetylation processes. The electronic absorption peak (400 nm) denoting surface plasmonic resonance of Ag NPs and infrared peaks relevant to CS (3364 cm-1 of OH/NH2, 2932 cm-1 of CH, and 1647 cm-1 of -CO) exhibited peaks confirmed the formation of CS-Ag NPs. Ag NPs-CS exhibited anticancer activity against Human lung adenocarcinoma cell lines (A549), the maximum cell death noticed at the concentration of 20 µg/mL and 70 µg/mL was 20 and 52 %, respectively. An aqueous Ag NPs-CS (100 µg/mL) was degraded ≥95 % of mixed dye target solution (25 mg/mL) containing equal volume of cationic dye (Methylene blue and Rhodamine B) and anionic dye (methyl orange). Therefore, these findings suggest that the shrimp shell waste derived CS can be used for the synthesis of CS-Ag NPs with potential biomedical and environmental applications.


Assuntos
Quitosana , Nanopartículas Metálicas , Humanos , Nanopartículas Metálicas/química , Quitosana/química , Prata/química , Luz Solar , Temperatura
13.
Chemosphere ; 341: 140012, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37652243

RESUMO

In the field of electrocatalysis, single-atomic-layer tungsten, copper, and cobalt oxide on CeO2, ethylene diamine (ED) and reduced graphene oxide (rGO) supported materials shows tremendous potential. Despite the enormous interest in single metal atom oxide (SMAO) catalysts, it is still very difficult to directly convert readily available bulk metal oxide into single atom oxide. It is crucial and tough to create high performance materials for the oxygen evolution reaction (OER) in an alkaline environment. Herein, a single tungsten, copper and cobalt atom oxide (SMAO) anchored on the CeO2 atomic layer and overall components deposited on the rGO (rGO-ED-CeO2-WCuCo) is prepared through a one-pot sonication technique. The presence of SMAO is identified by high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) imaging. The electrocatalytic performance of final rGO-ED-CeO2-WCuCo-30 nanocomposite for the OER in 1 M KOH electrolyte is evidenced by providing low overpotential of 283 mV at 10 mA cm-2. The Tafel slope for OER using rGO-ED-CeO2-WCuCo-30 electrocatalysts is 57.03 mV dec-1. The electrocatalytic activity of rGO-ED-CeO2-WCuCo-30 nanocomposites for OER was noticeably increased when compared to bare CeO2 nanorods (401 mV), rGO-ED-CeO2-WCo-30 (345 mV), rGO-ED-CeO2-WCu-30 (340 mV) and rGO-ED-CeO2-WCuCo-20 (321 mV) samples.


Assuntos
Cobre , Sonicação , Tungstênio , Óxidos , Oxigênio
14.
Micromachines (Basel) ; 14(7)2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37512635

RESUMO

Good water quality is essential for life; therefore, decolorizing and detoxifying organic dye wastes (textile effluents) have gained immense environmental importance in recent years. Thus, the degradation of wastewater has become a potential need for our environment. This research aims to synthesize and investigate a ceramic-based nanomaterial catalyst for the degradation of dye solution under exposure to sunlight. A reduced graphene oxide-ZnS (rGO-ZnS) nanomaterial was qualitatively synthesized using a solvothermal method. The prepared nanomaterial was characterized using XRD, SEM, HR-TEM, EDX, XPS, and FT-IR techniques. The photocatalytic activity of the rGO-ZnS nanomaterial was checked using oxidative photocatalytic degradation of naphthol blue black dye (NBB) under direct sunlight irradiation. Here, the rGO/ZnS composite showed a significant photocatalytic performance to degraded NBB (93.7%) under direct solar light. Chemical Oxygen Demand (COD) measurements confirmed the mineralization of the dye. The influence of different radical scavengers on NBB degradation was studied. Optimum conditions for efficient degradation were determined. The antibacterial property of the prepared catalyst was studied.

15.
Gels ; 9(7)2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37504464

RESUMO

Gel polymer electrolytes (GPEs) hold tremendous potential for advancing high-energy-density and safe rechargeable solid-state batteries, making them a transformative technology for advancing electric vehicles. GPEs offer high ionic conductivity and mechanical stability, enabling their use in quasi-solid-state batteries that combine solid-state interfaces with liquid-like behavior. Various GPEs based on different materials, including flame-retardant GPEs, dendrite-free polymer gel electrolytes, hybrid solid-state batteries, and 3D printable GPEs, have been developed. Significant efforts have also been directed toward improving the interface between GPEs and electrodes. The integration of gel-based electrolytes into solid-state electrochemical devices has the potential to revolutionize energy storage solutions by offering improved efficiency and reliability. These advancements find applications across diverse industries, particularly in electric vehicles and renewable energy. This review comprehensively discusses the potential of GPEs as solid-state electrolytes for diverse battery systems, such as lithium-ion batteries (LiBs), lithium metal batteries (LMBs), lithium-oxygen batteries, lithium-sulfur batteries, zinc-based batteries, sodium-ion batteries, and dual-ion batteries. This review highlights the materials being explored for GPE development, including polymers, inorganic compounds, and ionic liquids. Furthermore, it underscores the transformative impact of GPEs on solid-state batteries and their role in enhancing the performance and safety of energy storage devices.

16.
Chemosphere ; 338: 139513, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37454984

RESUMO

An effective catalyst for the removal of antibiotic pollutants which severely impact water bodies and the environment is most favorable. In this study, g-C3N4 (gCN) and nitrogen-doped Bi2MoO6 (gCN-NBM) heterostructures are developed using a solvothermal process with enhanced photocatalytic degradation of tetracycline (TC) pollutants under visible-light irradiation. The experimental results confirm that nitrogen-doped Bi2MoO6 (NBM) nanomaterials were dispersed on the gCN surface, and a close combination of NBM and gCN leads to the efficient photocatalytic performance of TC. The photocatalytic efficiency of the heterostructure catalysts is four-fold higher than those of the pristine Bi2MoO6 catalysts owing to the excellent photogenerated charge separation and reduced recombination rate. Photocurrent measurements and electrochemical impedance spectra results disclose that the prepared heterostructure catalysts exhibit efficient photo-induced charge transfer. The electron spin resonance spectra and quenching experiments results reveal that superoxide radicals (.O2-) play a major role in TC degradation. This study presents a promising approach for designing efficient visible-light photocatalysts for environmental remediation applications.


Assuntos
Poluentes Ambientais , Compostos Heterocíclicos , Tetraciclina , Antibacterianos , Bismuto , Luz , Catálise
17.
Environ Res ; 233: 116431, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37329946

RESUMO

In this study, we synthesized silver nanoparticle-loaded cashew nut shell activated carbon (Ag/CNSAC). The synthesized samples were characterized by XRD, XPS, SEM with EDS, FT-IR, and BET analysis. The XRD, XPS, and EDS data provided convincing proof that Ag loaded on CNSAC is formed. The energy dispersive spectrum analysis and X-ray diffraction pattern both supported the face-centered cubic and amorphous structures of Ag/CNSAC. The SEM micrographs showed the inner surface development of Ag NPs and many tiny pores in CNSAC. The photodegradation of methylene blue (MB) dye by the Ag/CNSAC photocatalyst was investigated. This effective degradation of MB dye by Ag/CNSAC is attributed to the cooperative action of Ag as a photocatalyst and CNSAC as a catalytic support and adsorbent. In tests with gram-positive and negative bacteria including Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), the as-synthesized Ag/CNSAC showed outstanding antibacterial efficiency. Additionally, this study demonstrates a workable procedure for creating an affordable and efficient Ag/CNSAC for the photocatalytic eradication of organic contaminants.


Assuntos
Nanopartículas Metálicas , Prata , Prata/farmacologia , Prata/química , Nanopartículas Metálicas/química , Carvão Vegetal , Espectroscopia de Infravermelho com Transformada de Fourier , Escherichia coli , Staphylococcus aureus , Antibacterianos/farmacologia , Antibacterianos/química , Difração de Raios X
18.
Membranes (Basel) ; 13(6)2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37367785

RESUMO

Developing a hybrid composite polymer membrane with desired functional and intrinsic properties has gained significant consideration in the fabrication of proton exchange membranes for microbial fuel cell applications. Among the different polymers, a naturally derived cellulose biopolymer has excellent benefits over synthetic polymers derived from petrochemical byproducts. However, the inferior physicochemical, thermal, and mechanical properties of biopolymers limit their benefits. In this study, we developed a new hybrid polymer composite of a semi-synthetic cellulose acetate (CA) polymer derivate incorporated with inorganic silica (SiO2) nanoparticles, with or without a sulfonation (-SO3H) functional group (sSiO2). The excellent composite membrane formation was further improved by adding a plasticizer (glycerol (G)) and optimized by varying the SiO2 concentration in the polymer membrane matrix. The composite membrane's effectively improved physicochemical properties (water uptake, swelling ratio, proton conductivity, and ion exchange capacity) were identified because of the intramolecular bonding between the cellulose acetate, SiO2, and plasticizer. The proton (H+) transfer properties were exhibited in the composite membrane by incorporating sSiO2. The composite CAG-2% sSiO2 membrane exhibited a higher proton conductivity (6.4 mS/cm) than the pristine CA membrane. The homogeneous incorporation of SiO2 inorganic additives in the polymer matrix provided excellent mechanical properties. Due to the enhancement of the physicochemical, thermal, and mechanical properties, CAG-sSiO2 can effectively be considered an eco-friendly, low-cost, and efficient proton exchange membrane for enhancing MFC performance.

19.
J Biomater Sci Polym Ed ; 34(14): 1911-1927, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37042185

RESUMO

In the past 15 years or more, interest in polymer-mediated nanofibers (NFs), a significant class of nanomaterials, has grown. Although fibers with a diameter of less than 1 mm are frequently commonly referred to as NFs, and are typically defined as having a diameter of less than several hundreds of nanometers. Due to the increased antibiotic resistance of many diseases nowadays, NFs with antibacterial activity are quite important. A flexible technique for creating NFs with the desired characteristics is called electrospinning. This research article describes how to make electrospun NFs of tannic acid (TA) with polyvinylidene fluoride (PVDF) as the template. As a result, the absorbance of the obtained NFs has been raised without forming any additional peaks in the spectral ranges. The obtained NF has a gradual increase in intensity, and the FT-IR data show that the TA is present in the NFs. FE-SEM images show that the NFs are discovered to be completely bead-free. Since TA reduced the viscosity of the spinning solution while marginally increasing solution conductivity, PVDF NFs have a greater average fiber diameter (AFD) than NFs of TA with PVDF, which is likely a result of the TA solutions in it. The findings showed that TA greatly decreased S. aureus and E. coli's ability to attach. The acquired NFs created in this work may have significant potential for reducing the pathogenicity of S. aureus and E. coli as well as their ability to build biofilms.


Assuntos
Nanofibras , Staphylococcus aureus , Escherichia coli , Espectroscopia de Infravermelho com Transformada de Fourier , Antibacterianos/farmacologia
20.
J Mol Struct ; 1285: 135461, 2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37041803

RESUMO

The respiratory infection tuberculosis is caused by the bacteria Mycobacterium tuberculosis and its unrelenting spread caused millions of deaths around the world. Hence, it is needed to explore potential and less toxic anti-tubercular drugs. In the present work, we report the synthesis and antitubercular activity of four different (hydrazones 7-12, O-ethynyl oximes 19-24, triazoles 25-30, and isoxazoles 31-36) hybrids. Among these hybrids 9, 10, 33, and 34, displayed high antitubercular activity at 3.12 g/mL with >90% of inhibitions. The hybrids also showed good docking energies between -6.8 and -7.8 kcal/mol. Further, most active molecules were assayed for their DNA gyrase reduction ability towards M. tuberculosis and E.coli DNA gyrase by the DNA supercoiling and ATPase gyrase assay methods. All four hybrids showed good IC50 values comparable to that of the reference drug. In addition, the targets were also predicted as a potential binder for papain-like protease (SARS CoV-2 PLpro) by molecular docking and a good interaction result was observed. Besides, all targets were predicted for their absorption, distribution, metabolism, and excretion - toxicity (ADMET) profile and found a significant amount of ADMET and bioavailability.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA