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1.
Mikrochim Acta ; 191(9): 540, 2024 08 16.
Article in English | MEDLINE | ID: mdl-39150580

ABSTRACT

For the first time the sensitive determination of carbendatim (CRB) is reported utilizing a well-designed sensing architecture based on vanadium diselenide-multiwalled carbon nanotube (VSMC). FTIR, XRD, FESEM, EDS, and EIS were employed to evaluate the sensor's structural integrity, and the results demonstrated the successful integration of nanomaterials, resulting in a robust and sensitive electrochemical sensor. Cyclic voltammetry (CV) and chronoamperometric (CA) investigations showed that the sensor best performed at pH 8.0 (BRB) with an excellent detection limit of 9.80 nM with a wide linear range of 0.1 to 10.0 µM. A more thermodynamically viable oxidation of CRB was observed at the VSMC/GCE, with a shift of 200 mV in peak potential towards the less positive side compared with the unmodified GCE. In addition, the sensor demonstrated facile heterogeneous electron transfer, favorable anti-fouling traits in the presence of a wide range of interferents, good stability, and reproducible analytical performance. Finally, the developed sensor was validated for real-time quantification of CRB from spiked water, food, and bio-samples, which depicted acceptable recoveries (98.6 to 101.5%) with RSD values between 0.35 and 2.23%. Further, to derive the possible sensing mechanism, the valence orbitals projected density of states (PDOS) for C, H, and N atoms of an isolated CRB molecule, VSe2 + CNT and VSe2 + CNT + CRB were calculated using density functional theory (DFT) calculations. The dominant charge transfer from the valence 2p-orbitals of the C and N atoms of CRB to CNT is responsible for the electrochemical sensing of CRB molecules.


Subject(s)
Benzimidazoles , Carbamates , Electrochemical Techniques , Limit of Detection , Nanotubes, Carbon , Nanotubes, Carbon/chemistry , Electrochemical Techniques/methods , Electrochemical Techniques/instrumentation , Carbamates/analysis , Carbamates/chemistry , Benzimidazoles/chemistry , Benzimidazoles/analysis , Food Contamination/analysis , Electrodes , Water Pollutants, Chemical/analysis , Animals
2.
Biotechnol Lett ; 46(4): 559-569, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38748066

ABSTRACT

The effective recovery of the immobilized enzymes using magnetic carriers has led to growing interest in this technology. The objective of this research was to evaluate the efficiency of immobilized laccase on magnetized multiwall carbon nanotubes (m-MWCNTs) in terms of stability and reusability. Laccases were efficiently adsorbed onto magnetized multiwall carbon nanotubes (m-MWCNTs) synthesized using water. The concentration of 7 mg laccase/mL was found to be ideal for immobilization. The optimal activity of both free and immobilized laccases was observed at pH 5, while for the latter, the optimal temperature was shifted from 40 to 50 °C. Compared to the free laccase, the immobilized laccase exhibited a greater range of stability at more extreme temperatures. At the fourth cycle of reactions, the immobilized laccase exhibited more than 60% relative activity in terms of reusability. Based on the fourier-transform infrared spectroscopy (FTIR) peak at 2921 cm-1, saccharification of paddy straw using immobilized laccase verified lignin degradation. The easy recovery of the immobilized laccase on m-MWCNTs lends credence to its potential use in biomass hydrolysis.


Subject(s)
Enzymes, Immobilized , Laccase , Nanotubes, Carbon , Laccase/chemistry , Laccase/metabolism , Enzymes, Immobilized/chemistry , Enzymes, Immobilized/metabolism , Nanotubes, Carbon/chemistry , Hydrogen-Ion Concentration , Enzyme Stability , Temperature , Lignin/chemistry , Lignin/metabolism , Oryza/chemistry
3.
Heliyon ; 10(4): e26693, 2024 Feb 29.
Article in English | MEDLINE | ID: mdl-38434029

ABSTRACT

The integration of surface-modified multiwalled carbon nanotubes (fMWCNTs) into polymer nanocomposites has been extensively studied for their potential to enhance dielectric properties. This study, however, pioneers the use of a novel hybrid filler comprising fMWCNTs coated with metal nanoparticles, specifically aimed at augmenting the dielectric performance of polymers. In our research, poly(vinylidene fluoride) (PVDF) nanocomposite films were synthesized using fMWCNTs with a diameter of ∼6-9 nm and a length of 5 µm, adorned with gold nanoparticles (nAu) of ∼5.4 ± 0.9 nm via an adapted Turkevich method. Comprehensive analyses were conducted on nAu-fMWCNTs hybrid powder and their nanocomposites in PVDF with varying filler concentrations, confirming the formation of nAu-fMWCNTs with a weight ratio of 1.1 : 98.9. Three-phase percolative nanocomposites were produced by dispersing the hybrid filler in N,N-dimethylformamide, facilitated by interactions between the negative charge of nAu-fMWCNTs (zeta potential of âˆ¼ -40.43 ± 0.46 mV) and polar phases of PVDF. This was verified through zeta potential and Fourier-transform infrared spectroscopy analyses. The dielectric permittivity (ε') of the nanocomposites significantly increased from 17.8 to 524.8 (at 1 kHz) with filler loadings from 0.005 to 0.01 vol%, while the dielectric loss tangent (tanδ) showed a minor increase from 0.05 to 1.18. These enhancements are attributed to the elevated permittivity of nAu-fMWCNTs hybrid powder, PVDF's transition to the ß-phase, and interfacial polarization effects. The restrained growth of nAu on fMWCNTs and the inhibition of conductive pathways in the polymer matrix contributed to the low tanδ values.

4.
Materials (Basel) ; 17(4)2024 Feb 19.
Article in English | MEDLINE | ID: mdl-38399216

ABSTRACT

This work presents a proposal for an adsorptive stripping voltammetric (AdSV) method for gallium(III) determination at an eco-friendly multiwall carbon nanotube/spherical glassy carbon (MWCNT/SGC) electrode modified with a lead film. The operational factors influencing the sensitivity of the AdSV procedure were thoroughly investigated, and their most favorable values were chosen (0.1 mol L-1 acetate buffer solution pH = 5.6; 7 × 10-5 mol L-1 Pb(II); 2 × 10-4 mol L-1 cupferron; potential/time of lead film formation: -1.9 V/30 s; potential/time of Ga(III)-cupferron adsorption: -0.75 V/30 s). The newly developed MWCNT/SGCE has proven to be a competitive substrate to the glassy carbon electrode to create a lead film electrode, since it allows the determination of gallium in a wider range of concentrations from 3 × 10-9 to 4 × 10-7 mol L-1 with a lower limit of detection equal to 9.5 × 10-10 mol L-1. The elaborated procedure has been shown to be highly selective and insensitive to the presence of an even 100-fold excess of most of the ions commonly found in environmental waters. The MWCNT/SGC sensor, which can maintain >95% of its original response after 70 days of use, has been successfully applied for the detection of gallium in water samples with the relative standard deviation (RSD) ranging from 4.5% to 6.2% (n = 3) and recoveries in the range from 95.3% to 104.9%.

5.
Nanomaterials (Basel) ; 14(3)2024 Feb 02.
Article in English | MEDLINE | ID: mdl-38334576

ABSTRACT

New and efficient sensors of nerve agents are urgently demanded to prevent them from causing mass casualties in war or terrorist attacks. So, in this work, a novel hierarchical nanoheterostructure was synthesized via the direct growth of α-Fe2O3 nanorods onto multiwall carbon nanotube (MWCNT) backbones. Then, the composites were functionalized with hexafluoroisopropanol (HFIP) and successfully applied to detect dimethyl methylphosphonate (DMMP)-sarin simulant gas. The observations show that the HFIP-α-Fe2O3@MWCNT hybrids exhibit outstanding DMMP-sensing performance, including low operating temperature (220 °C), high response (6.0 to 0.1 ppm DMMP), short response/recovery time (8.7 s/11.9 s), as well as low detection limit (63.92 ppb). The analysis of the sensing mechanism demonstrates that the perfect sensing performance is mainly due to the synergistic effect of the chemical interaction of DMMP with the heterostructure and the physical adsorption of DMMP by hydrogen bonds with HFIP that are grafted on the α-Fe2O3@MWCNTs composite. The huge specific surface area of HFIP-α-Fe2O3@MWCNTs composite is also one of the reasons for this enhanced performance. This work not only offers a promising and effective method for synthesizing sensitive materials for high-performance gas sensors but also provides insight into the sensing mechanism of DMMP.

6.
Appl Biochem Biotechnol ; 196(3): 1544-1557, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37432637

ABSTRACT

A well-developed-multiwall carbon nanotube (f-MWCNT)/biphasic calcium phosphate (BCP) composites were synthesized using ultrasonication method for orthopedic implantation applications. The formation of composites and its phase was confirmed by using X-ray diffraction. The presence of various functional groups was identified by using Fourier transform infra-red (FT-IR) spectroscopy. The presence of f-MWCNT was confirmed by Raman spectroscopy. High-resolution transmission electron microscopy (HR-TEM) analysis revealed that BCP units were bound by the surface of f-MWCNTs. The synthesized composites were coated on medical grade 316L stainless steel substrates using electro deposition technique. To determine its corrosion resistance characteristics, the developed substrates were exposed to a simulated bodily fluid (SBF) solution for 0, 4, and 7 days. These results strongly suggest that the coated composites can be utilized for bone tissue repair.


Subject(s)
Body Fluids , Hydroxyapatites , Stainless Steel , Stainless Steel/chemistry , Materials Testing , Corrosion , Spectroscopy, Fourier Transform Infrared
7.
Polymers (Basel) ; 15(22)2023 Nov 14.
Article in English | MEDLINE | ID: mdl-38006128

ABSTRACT

Recently, piezoresistive sensors made by 3D printing have gained considerable interest in the field of wearable electronics due to their ultralight nature, high compressibility, robustness, and excellent electromechanical properties. In this work, building on previous results on the Selective Laser Sintering (SLS) of porous systems based on thermoplastic polyurethane (TPU) and graphene (GE)/carbon nanotubes (MWCNT) as carbon conductive fillers, the effect of variables such as thickness, diameter, and porosity of 3D printed disks is thoroughly studied with the aim of optimizing their piezoresistive performance. The resulting system is a disk with a diameter of 13 mm and a thickness of 0.3 mm endowed with optimal reproducibility, sensitivity, and linearity of the electrical signal. Dynamic compressive strength tests conducted on the proposed 3D printed sensors reveal a linear piezoresistive response in the range of 0.1-2 N compressive load. In addition, the optimized system is characterized at a high load frequency (2 Hz), and the stability and sensitivity of the electrical signal are evaluated. Finally, an application test demonstrates the ability of this system to be used as a real-time wearable pressure sensor for applications in prosthetics, consumer products, and personalized health-monitoring systems.

8.
Toxicol Sci ; 196(1): 85-98, 2023 10 30.
Article in English | MEDLINE | ID: mdl-37584706

ABSTRACT

The widespread use of nanomaterials in daily life has led to increased concern about their potential neurotoxicity. Therefore, it is particularly important to establish a simple and reproducible assessment system. Representative nanomaterials, including cobalt nanoparticles (CoNPs), titanium dioxide nanoparticles (TiO2-NPs), and multiwall carbon nanotubes (MWCNTs), were compared in terms of their neurotoxicity and underlying mechanisms. In 0, 25, 50, and 75 µg/ml of these nanomaterials, the survival, locomotion behaviors, acetylcholinesterase (AchE) activity, reactive oxygen species production, and glutathione-S transferase 4 (Gst-4) activation in wildtype and transgenic Caenorhabditis elegans (C. elegans) were evaluated. All nanomaterials induced an imbalance in oxidative stress, decreased the ratio of survival, impaired locomotion behaviors, as well as reduced the activity of AchE in C. elegans. Interestingly, CoNPs and MWCNTs activated Gst-4, but not TiO2-NPs. The reactive oxygen species scavenger, N-acetyl-l-cysteine, alleviated oxidative stress and Gst-4 upregulation upon exposure to CoNPs and MWCNTs, and rescued the locomotion behaviors. MWCNTs caused the most severe damage, followed by CoNPs and TiO2-NPs. Furthermore, oxidative stress and subsequent activation of Gst-4 were involved in nanomaterials-induced neurotoxicity. Our study provides a comprehensive comparison of the neurotoxicity and mechanisms of typical nanomaterials, which could serve as a model for hazard assessment of environmental pollutants using C. elegans as an experimental model system.


Subject(s)
Nanoparticles , Nanotubes, Carbon , Animals , Reactive Oxygen Species , Caenorhabditis elegans , Nanotubes, Carbon/toxicity , Cobalt/toxicity , Acetylcholinesterase , Oxidative Stress , Nanoparticles/toxicity
9.
Toxics ; 11(4)2023 Apr 14.
Article in English | MEDLINE | ID: mdl-37112600

ABSTRACT

Carbon nanotubes (CNTs) have gained much attention due to their superb properties, which make them promising options for the reinforcing composite materials with desirable mechanical properties. However, little is known about the linkage between lung exposure to nanomaterials and kidney disease. In this study, we compared the effects on the kidneys and aging for two different types of multiwall carbon nanotubes (MWCNTs): pristine MWCNTs (PMWCNTs) and acid-treated MWCNTs (TMWCNTs), with TMWCNTs being the preferred form for use as a composite material due to its superior dispersion properties. We used tracheal instillation and maximum tolerated dose (MTD) for both types of CNTs. MTD was determined as a 10% weight loss dose in a 3-month subchronic study, and the appropriate dosage for 1-year exposure was 0.1 mg/mouse. Serum and kidney samples were analyzed using ELISA, Western blot, and immunohistochemistry after 6 months and 1 year of treatment. PMWCNT-administered mice showed the activation of pathways for inflammation, apoptosis, and insufficient autophagy, as well as decreased serum Klotho levels and increased serum levels of DKK-1, FGF-23, and sclerostin, while TMWCNTs did not. Our study suggests that lung exposure to PMWCNTs can induce premature kidney aging and highlights a possible toxic effect of using MWCNTs on the kidneys in the industrial field, further highlighting that dispersibility can affect the toxicity of the nanotubes.

10.
Materials (Basel) ; 16(8)2023 Apr 20.
Article in English | MEDLINE | ID: mdl-37110088

ABSTRACT

The practical application of a novel, eco-friendly electrochemical sensor based on low-dimensional structures, spherical glassy carbon microparticles, and multiwall carbon nanotubes is described. This sensor, modified with a bismuth film, was used for the determination of Cd(II) by the anodic stripping voltammetric method. The instrumental and chemical factors influencing the sensitivity of the procedure were thoroughly investigated and their most favorable values were selected (acetate buffer solution pH = 3 ± 0.1; 0.15 mmol L-1 Bi(III); activation potential/time: -2 V/3 s; accumulation potential/time: -0.9 V/50 s). Under the selected conditions, the method exhibited linearity in the range of 2 × 10-9 to 2 × 10-7 mol L-1 Cd(II) with a detection limit of 6.2 × 10-10 mol L-1 Cd(II). The results obtained also showed that the application of the sensor for Cd(II) detection did not experience any significant interference in the presence of a number of foreign ions. The applicability of this procedure was evaluated using TM-25.5 Environmental Matrix Reference Material and SPS-WW1 Waste Water Certified Reference Material as well as river water samples through addition and recovery tests.

11.
Polymers (Basel) ; 15(5)2023 Feb 27.
Article in English | MEDLINE | ID: mdl-36904431

ABSTRACT

In this particular research study, a unique three-dimensional mixing technique was used to incorporate multi-walled carbon nanotubes (MWCNTs) into polymethyl methacrylate (PMMA), and the KB cell line was used in the analysis of cytotoxicity, apoptosis detection, and cell viability using the MTT assay protocol. At low concentrations (0.001 to 0.1 g/mL), these results showed that the CNT did not seem to cause cell death or apoptosis directly. It increased lymphocyte-mediated cytotoxicity against KB cell lines. This was demonstrated by the fact that the CNT increased the time it took for KB cell lines to die. In the end, the unique three-dimensional mixing method solves problems such as clumping and uneven mixing that have been written about in the relevant literature. Phagocytic uptake of MWCNT-reinforced PMMA nanocomposite by KB cells leads to oxidative stress and apoptosis induction in a dose-dependent manner. The cytotoxicity of the generated composite and the ROS (reactive oxygen species) it produces may be controlled by adjusting the MWCNT loading. The conclusion that can be drawn from the studies to date is that it could be possible to treat some types of cancer using PMMA that has MWCNTs incorporated into it.

12.
Polymers (Basel) ; 15(23)2023 Nov 26.
Article in English | MEDLINE | ID: mdl-38231944

ABSTRACT

This work is devoted to the development of epoxy-encapsulated zinc oxide-multiwalled carbon nanotubes (ZnO-MWCNT) hybrid nanostructured composites and the investigation of their thermoelectric performance in relation to the content of MWCNTs in the composite. For the preparation of nanocomposites, self-assembling Zn nanostructured networks were coated with a layer of dispersed MWCNTs and subjected to thermal oxidation. The resulting ZnO-MWCNT hybrid nanostructured networks were encapsulated in commercially available epoxy adhesive. It was found that encapsulation of ZnO-MWCNT hybrid networks in epoxy adhesive resulted in a simultaneous decrease in their electrical resistance by a factor of 20-60 and an increase in the Seebeck coefficient by a factor of 3-15, depending on the MWCNT content. As a result, the thermoelectric power factor of the epoxy-encapsulated ZnO-MWCNTs hybrid networks exceeded that of non-encapsulated networks by more than 3-4 orders of magnitude. This effect was attributed to the ZnO-epoxy interface's unique properties and to the MWCNTs' contribution. The processes underlying such a significant improvement of the properties of ZnO-MWCNT hybrid nanostructured networks after encapsulation in epoxy adhesive are discussed. In addition, a two-leg thermoelectric generator composed of epoxy-encapsulated ZnO-MWCNT hybrid nanocomposite as n-type leg and polydimethylsiloxane-encapsulated CuO-MWCNT hybrid nanocomposite as p-type leg characterized at room temperatures showed better performance at temperature difference 30 °C compared with the similar devices, thus proving the potential of the developed nanocomposites for applications in domestic waste heat conversion devices.

13.
ACS Sens ; 7(12): 3846-3856, 2022 Dec 23.
Article in English | MEDLINE | ID: mdl-36507663

ABSTRACT

Metal-organic frameworks (MOFs) present specific adsorption sites with varying electron affinity which are uniquely conducive to selective gas sensing but are typically large-band-gap insulators. On the contrary, multiwall carbon nanotubes (MWCNTs) exhibit superior mesoscopic transport exploiting strong electron correlations among sub-bands below and above the Fermi level at room temperature. We synergize them in a new class of nanocomposites based on zeolitic imidazolate framework-8 (ZIF-8) and report selective sensing of CH4 in ∼10 parts-per-billion (ppb) with a determined limit of detection of ∼0.22 ppb, hitherto unprecedented. The observed selectivity to CH4 over non-polar CO2, polar volatile organic compounds, and moisture has roots in competing electron-sharing mechanisms at its different adsorption sites. This important result provides a significant reference to guide future MOF-related composite research to achieve the best sensing performance. On molecular adsorption, MWCNTs facilitate electrical transport via manipulating the ZIF-8 band gap to show a p-type semiconductor behavior with lower activation energy to induce a measurable resistance change. Excellent repeatability and reversibility are shown. A carbon-engineered MOF composite has the potential to actuate similar selective response to low reactive gases via carrier manipulation in the energy band gap.

14.
Materials (Basel) ; 15(24)2022 Dec 15.
Article in English | MEDLINE | ID: mdl-36556763

ABSTRACT

High filled polylactide/multiwall carbon nanotube composites were subjected to multiple extrusions using single-screw and twin-screw extruders. Samples of the processed composites were characterized by SEM, XRD, Raman, and FTIR spectroscopy. Thermal and rheological properties were investigated by DSC and MFR analyses. Subsequent extrusions resulted in decreased torque and process efficiency, which is a consequence of the viscosity reduction of PLA. Thermal and rheological properties of composites changed after each extrusion as well. As revealed by DSC analyses, cold crystallization temperature showed a tendency to decrease after each process, whereas cold crystallization enthalpy ΔHcc increased significantly. Melt flow rate, which is indicative of the polymer degradation, increased after each extrusion.

15.
Polymers (Basel) ; 14(23)2022 Nov 25.
Article in English | MEDLINE | ID: mdl-36501527

ABSTRACT

This work is devoted to the fabrication of p-type polyvinyl alcohol (PVA)-based flexible thermoelectric composites using multiwall carbon nanotubes-antimony telluride (MWCNT-Sb2Te3) hybrid filler, the study of the thermoelectrical and mechanical properties of these composites, and the application of these composites in two types (planar and radial) of thermoelectric generators (TEG) in combination with the previously reported PVA/MWCNT-Bi2Se3 flexible thermoelectric composites. While the power factors of PVA/MWCNT-Sb2Te3 and PVA/MWCNT-Bi2Se3 composites with 15 wt.% filler were found to be similar, the PVA/MWCNT-Sb2Te3 composite with 25 wt.% filler showed a ~2 times higher power factor in comparison with the PVA/MWCNT-Bi2Se3 composites with 30 wt.% filler, which is attributed to its reduced electrical resistivity. In addition, developed PVA/MWCNT-Sb2Te3 composites showed a superior mechanical, electrical, and thermoelectric stability during 100 consequent bending cycles down to a 3 mm radius, with insignificant fluctuations of the resistance within 0.01% of the initial resistance value of the not bent sample. Demonstrated for the first time, 2-leg TEGs composed from p-type PVA/MWCNT-Sb2Te3 and n-type PVA/MWCNT-Bi2Se3 composites showed a stable performance under different external loads and showed their potential for applications involving low temperature gradients and power requirements in the range of nW.

16.
Nanomaterials (Basel) ; 12(19)2022 Oct 10.
Article in English | MEDLINE | ID: mdl-36234663

ABSTRACT

This article explores the industrial application of an Al-based nanocomposite reinforced with 0.5 wt.% of multiwalled carbon nanotubes with a Zn mechanical plating applied to fulfill the field requirements of electrical devices. The performance of electric devices made from this nanocomposite material and with a Zn plating was compared with that of MCCB devices using a normal Cu compound. MCCB devices with the Al-based nanocomposites compound showed a better performance, with less heat generated due to a flow of electrical charge passing through the device. The presence of MWCNTs in the Al nanocomposite dissipates heat, maintaining a stable electrical resistance in the MCCB, in contrast to what happens with Cu compound, which increases its electrical resistance as the temperature in the device increases.

17.
Micromachines (Basel) ; 13(9)2022 Sep 05.
Article in English | MEDLINE | ID: mdl-36144093

ABSTRACT

Currently, there is an increasing demand for portable and wearable electronics. This has necessitated the development of stretchable energy storage devices, while simultaneously maintaining performance. Hence, the electrodes and electrolyte materials used in stretchable supercapacitors should be robust under severe mechanical deformation. Polymers are widely used in the fabrication of stretchable supercapacitors. It is not only crucial to choose good polymer candidates with inherent advantages, but it is also important to design suitable polymer materials for both electrodes and electrolytes. This mini-review explains the concept of stretchable supercapacitors, the theoretical background of polymer-based electrodes for supercapacitors, and the fabrication strategies of stretchable electrodes for supercapacitors. Finally, we present the drawbacks and areas that still need to be developed.

18.
Polymers (Basel) ; 14(18)2022 Sep 19.
Article in English | MEDLINE | ID: mdl-36146066

ABSTRACT

For the photocatalytic removal of the Reactive Blue 4 dye from an aqueous stream, new polyaniline/multi walled carbon nanotube nanocomposites (PANI-MWCNTs) were applied as a promising photocatalyst. The PANI-MWCNT nanocomposites were fabricated by aniline oxidation in the presence of MWCNTs using the typical direct oxidation polymerization route. The morphology, the Fourier transform infrared (FTIR) spectra and the UV-Vis absorbance spectra of the fabricated nanocomposites were studied and the attained data confirmed the good interaction between the MWCNTs and PANI matrix. The PANI-MWCNTs nanocomposites were varied according to the wt%, the MWCNTs, which ranged from 0-10 wt% and the corresponding resultant samples are labeled as P-0, P-3, P-5, P-5, P-7 and P-10, respectively. Such composites showed the high potential for the removal of the Reactive Blue 4 dye containing pollutants from wastewater. The starting concentration of the dye pollutants was halved during the first 5 min of UV illumination. The oxidation technique of Reactive Blue 4 over the prepared nanocomposites were processed in a different way and the highest catalytic activity corresponded to P-7. The process reached the complete dye removal in low concentrations of contaminants. The kinetics of the removal followed the pseudo-second order regime which possesses high correlation coefficients with the k2 in the range of 0.0036-0.1115 L.mg-1.min-1 for the Reactive Blue 4 oxidation. In this regard, the combination of the PANI and MWCNTs showed a superior novel photocatalytic activity in the oxidation of commercial textile dying wastewater, namely Reactive Blue 4. This study is the starting point for future applications on an industrial scale since the successful performances of the PANI-MWCNT on commercial dye oxidation.

19.
Nanomaterials (Basel) ; 12(14)2022 Jul 14.
Article in English | MEDLINE | ID: mdl-35889642

ABSTRACT

Graphene nanoplatelets (GNPs) and multiwall carbon nanotubes (CNTs)-polypropylene (PP) composite materials for electromagnetic interference (EMI) shielding applications were fabricated as 1 mm thick panels and their properties were studied. Structural and morphologic characterization indicated that the obtained composite materials are not simple physical mixtures of these components but new materials with particular properties, the filler concentration and nature affecting the nanomaterials' structure and their conductivity. In the case of GNPs, their characteristics have a dramatic effect of their functionality, since they can lead to composites with lower conductivity and less effective EMI shielding. Regarding CNTs-PP composite panels, these were found to exhibit excellent EMI attenuation of more than 40 dB, for 10% CNTs concentration. The development of PP-based composite materials with added value and particular functionality (i.e., electrical conductivity and EMI shielding) is highly significant since PP is one of the most used polymers, the best for injection molding, and virtually infinitely recyclable.

20.
Steroids ; 186: 109091, 2022 10.
Article in English | MEDLINE | ID: mdl-35863403

ABSTRACT

Despite current medical advancements, the resistance of malignant tumours to conventional medical therapies highlights the need for innovative therapeutic techniques. Numerous studies have focused on the promising application of nanomaterials in recent years. Nanoparticles (NPs) are used to treat cancer. Plasmonic photothermal therapy (PPTT) is a cancer-ablation technique in which photon energy is rapidly converted into heat by some radiative and non-radiative events. Gold NPs (Au-NPs) and carbon nanotubes (CNTs) are plasmonic NPs with excellent thermal conductivity and their near-infrared (NIR) absorbance has several interesting qualities. Additionally, CNTs could penetrate cells. In this study, Au-NPs were used to fabricate multi-walled CNTs (MWCNTs), which could boost its efficacy in cancer treatment in accordance with PPTT. Transmission electron microscopy, field-emission scanning electron microscopy (FESEM), atomic force microscopy and FTIR were used to examine the MWCNTs made from walnut shell. Au-NPs were explored using green chemistry and MWCNT-COOAu, MWCNT-COO and MWCNT-Au were examined by Raman, EDX and FESEM techniques. The effect of MWCNT-COOAu, MWCNT-COO and MWCNT-Au at various concentrations (3.12, 6.25, 12.5 and 25 µg/mL) and irradiation time intervals (30, 60, 90 and 120 sec) by using NIR laser under λ = 1064 nm and P = 3 W on the breast cancer cell line (MCF7) was investigated. The highest temperatures for MWCNT-COO, MWCNT-COOAu and MWCNT-Au were determined to be 44.1 °C, 46 °C and 46.9 °C, respectively, which produced 61.66 %, 72 % and 85.3 % cytotoxicity, respectively, in MCF7 cell line at a concentration of 25 µg/mL and an irradiation period of 120 sec. The treatment of MCF7 cell line by photothermal therapy was found to be in a concentration- and time-dependent manner.


Subject(s)
Breast Neoplasms , Nanocomposites , Nanotubes, Carbon , Breast Neoplasms/therapy , Female , Gold , Humans , Nanocomposites/therapeutic use , Photothermal Therapy
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