scholarly journals Combining Carbon Nanotubes and Chitosan for the Vectorization of Methotrexate to Lung Cancer Cells

Materials ◽  
2019 ◽  
Vol 12 (18) ◽  
pp. 2889 ◽  
Author(s):  
Giuseppe Cirillo ◽  
Orazio Vittorio ◽  
David Kunhardt ◽  
Emanuele Valli ◽  
Florida Voli ◽  
...  

A hybrid system composed of multi-walled carbon nanotubes coated with chitosan was proposed as a pH-responsive carrier for the vectorization of methotrexate to lung cancer. The effective coating of the carbon nanostructure by chitosan, quantified (20% by weight) by thermogravimetric analysis, was assessed by combined scanning and transmission electron microscopy, and X-ray photoelectron spectroscopy (N1s signal), respectively. Furthermore, Raman spectroscopy was used to characterize the interaction between polysaccharide and carbon counterparts. Methotrexate was physically loaded onto the nanohybrid and the release profiles showed a pH-responsive behavior with higher and faster release in acidic (pH 5.0) vs. neutral (pH 7.4) environments. Empty nanoparticles were found to be highly biocompatible in either healthy (MRC-5) or cancerous (H1299) cells, with the nanocarrier being effective in reducing the drug toxicity on MRC-5 while enhancing the anticancer activity on H1299.

2014 ◽  
Vol 926-930 ◽  
pp. 258-261
Author(s):  
Jing Heng Deng ◽  
Kan Ping Yu ◽  
Jian Guo Xie

Hierarchical nanostructure Fe3O4/multi-walled carbon nanotubes (Fe3O4/MWCNTs) were prepared by solvothermal process using acid treated MWCNTs and iron acetylacetonate in ethylene glycol as reduction reagent. The materials were characterized using X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and Brunauer-Emmett-Teller (BET). The results showed that petal-like hierarchical Fe3O4 grew on MWCNTs and the Fe3O4 nanoparticles had diameters in the range of 55-110 nm. It was a facile approach to grow hierarchical nanoFe3O4.


2010 ◽  
Vol 117 ◽  
pp. 27-32
Author(s):  
Sabita Shrestha ◽  
Chong Yun Park

Titanium dioxide (Titania, TiO2) nanoparticles have been deposited on the surface of acid treated multi-walled carbon nanotubes (MWCNTs) by simple chemical route. The resultant TiO2/MWCNTs composites were characterized by different techniques. The oxidation of MWCNTs and presence of titania nanoparticles on the surface of MWCNTs is confirmed by transmission electron microscopy, energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy. TEM image shows the size of titania nanoparticles are around 5 nm. Raman spectroscopy showed the oxidation and functionalization of nanotubes. The TGA curve showed decrease in thermal decomposition temperature of MWCNTs after oxidation and attachment with titania nanoparticles.


2017 ◽  
Vol 52 (4) ◽  
pp. 449-464 ◽  
Author(s):  
Roger H Bello ◽  
Luiz AF Coelho ◽  
Daniela Becker

The effects of the silanization of multi-walled carbon nanotubes and graphene nanoplatelets with 3-APTES on thermal, mechanical and electrical properties of epoxy nanocomposites were investigated. Nanocomposites containing pristine, oxidized and silanized nanoparticles of multi-walled carbon nanotubes or graphene nanoplatelets at two different concentrations (0.15 and 0.50 vol.%) were prepared by in situ polymerization without using solvents. The functionalized nanoparticles were characterized by Fourier-transform infrared, X-ray photoelectron spectroscopy, Raman spectroscopy and transmission electron microscope techniques. The oxidation and the silanization on the surface of both nanoparticles were confirmed by Fourier-transform infrared, X-ray photoelectron spectroscopy, Raman and transmission electron microscope analysis. The thermal properties of all studied materials were analyzed by differential scanning calorimetry and the mechanical properties by nanoindentation. The addition of both nanoparticles (pristine and functionalized) into the matrix did not show significant variations on thermal properties, but decreased values for glass transition temperature (Tg) compared to the neat resin. Higher values for modulus of elasticity and hardness of epoxy/nanocomposites were obtained when silanized multi-walled carbon nanotubes or oxidized graphene nanoplatelets were added into the matrix. Adding 0.15 vol.% of silanized multi-walled carbon nanotubes the modulus of elasticity increased in approximately 60%, whereas 0.50 vol.% this increase was greater than 90% compared to the neat resin. While adding 0.15 vol.% of oxidized graphene nanoplatelets, the modulus of elasticity increased approximately 83%, whereas 0.50 vol.% this increase was greater than 88% compared to the neat resin. The formation of percolating networks has been achieved only by pristine multi-walled carbon nanotubes addition at a concentration of 0.50 vol.% and by silanized graphene nanoplatelets at a concentration of 0.15 vol.%. However, for both carbon-based nanoparticles conductivities on the order of 10−7 S/m for frequencies near 100 Hz were observed.


2012 ◽  
Vol 16 (07n08) ◽  
pp. 713-740 ◽  
Author(s):  
José H. Zagal ◽  
Sophie Griveau ◽  
Mireya Santander-Nelli ◽  
Silvia Gutierrez Granados ◽  
Fethi Bedioui

We discuss here the state of the art on hybrid materials made from single (SWCNT) or multi (MWCNT) walled carbon nanotubes and MN4complexes such as metalloporphyrins and metallophthalocyanines. The hybrid materials have been characterized by several methods such as cyclic voltammetry (CV), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM) and scanning electrochemical microscropy (SECM). The materials are employed for electrocatalysis of reactions such as oxygen and hydrogen peroxide reduction, nitric oxide oxidation, oxidation of thiols and other pollutants.


Nanomaterials ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 1410 ◽  
Author(s):  
den Hoed ◽  
Pucci ◽  
Picchioni ◽  
Raffa

Homogeneous water dispersions of multi-walled carbon nanotubes (MWCNTs) were prepared by ultrasonication in the presence of an amphiphilic polystyrene-block-poly(acrylic acid) (PS-b-PAA) copolymer. The ability of PS-b-PAA to disperse and stabilize MWCTNs was investigated by UV-vis, SEM and zeta potential. The results show that the addition of a styrene block to PAA enhances the dispersion efficiency of the graphitic filler compared to pure PAA, possibly due to the nanotube affinity with the polystyrene moiety. Notably, the dispersions show an evident pH-responsive behavior, being MWCNTs reaggregation promoted in basic environment. It is worth noting that the responsive character is maintained in solid composites obtained by drop casting, thus indicating potential applications in sensing.


Nanomaterials ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 2993
Author(s):  
Danil V. Sivkov ◽  
Olga V. Petrova ◽  
Sergey V. Nekipelov ◽  
Alexander S. Vinogradov ◽  
Roman N. Skandakov ◽  
...  

The results of the research of a composite based on multi-walled carbon nanotubes (MWCNTs) decorated with CuO/Cu2O/Cu nanoparticles deposited by the cupric formate pyrolysis are discussed. The study used a complementary set of methods, including scanning and transmission electron microscopy, X-ray diffractometry, Raman, and ultrasoft X-ray spectroscopy. The investigation results show the good adhesion between the copper nanoparticles coating and the MWCNT surface through the oxygen atom bridge formation between the carbon atoms of the MWCNT outer graphene layer and the oxygen atoms of CuO and Cu2O oxides. The formation of the Cu–O–C bond between the coating layer and the outer nanotube surface is clearly confirmed by the results of the O 1s near edge X-ray absorption fine structure (NEXAFS) and X-ray photoelectron spectroscopy (XPS) of the Cu/MWCNTs nanocomposite. The XPS measurements were performed using a laboratory spectrometer with sample charge compensation, and the NEXAFS studies were carried out using the synchrotron radiation of the Russian–German dipole beamline at BESSY-II (Berlin, Germany) and the NanoPES station at the Kurchatov Center for Synchrotron Radiation and Nanotechnology (Moscow, Russia).


2019 ◽  
Vol 5 (3) ◽  
pp. 54
Author(s):  
Alyona V. Gerasimova ◽  
Olga V. Alekhina ◽  
Leticia García-Cruz ◽  
Jesús Iniesta ◽  
Alexander V. Melezhik ◽  
...  

Aminocumulene (AC), a technical name that results from the hexamethylenetetramine polycondensation in anhydrous sulfuric acid, was successfully performed toward the synthesis of oligomeric cumulenic compounds made up of carbyne-like (=C=C)x fragments as a main moiety together with amino endcapping groups. The tentative mechanism for the synthesis of the soluble and insoluble AC likely included the participation of carbene species as an intermediate. Spectral properties obtained from UV-Vis, infrared, and Raman spectroscopies, and surface chemistry analysis through X-ray photoelectron spectroscopy of the soluble AC confirmed the presence of a mixture of linear and branched aminocumulene-based oligomers. AC displayed high performance as a dispersant and stabilizer agent of both multi-walled carbon nanotubes and graphene in aqueous solutions after powerful insonation treatment under controlled temperature compared to the most commonly used dispersant agents. Thereby, AC is vitally important for the preparation of carbonaceous materials based on nanoinks in a wide variety of fields.


2019 ◽  
Vol 79 (12) ◽  
pp. 2345-2356
Author(s):  
Jiye Yu ◽  
Xiaojun Tian ◽  
Mingwang Liu ◽  
Zhenzhen Jia ◽  
Hongqin Fang ◽  
...  

Abstract Heterogeneous Fenton oxidation has become a very important wastewater-treatment method and its catalyst is crucial for good treatment effect. In order to improve the catalytic properties, the Cu and Mn elements were doped for CuxMnxFe3-2xO4/multi-walled carbon nanotubes (CuxMnxFe3-2xO4/MWCNTs) nanocomposites (0 ≤ x ≤ 0.1) by co-precipitation method. The structure, morphology and surface properties of the nanocomposites were characterized by X-ray powder diffractometer (XRD), N2-physisorption analysis, transmission electron microscope (TEM), and X-ray photoelectron spectroscopy (XPS). The CuxMnxFe3-2xO4/MWCNTs nanocomposites were used as heterogeneous Fenton catalysts for p-nitrophenol (p-NP) degradation. The catalytic performances of the Cu and/or Mn doped nanocomposites have remarkable improvement compared with Fe3O4/MWCNTs nanocomposite, especially for both Cu and Mn doped catalyst. For CuxMnxFe3-2xO4/MWCNTs nanocomposites, the catalytic performance increases with increasing x value and reaches a maximum at 0.075 of x value. At optimal condition, the p-NP conversion rate reaches 96.4% in 10 min for Cu0.075Mn0.075Fe2.85O4/MWCNTs nanocomposite. However, the mentioned rate for Fe3O4/MWCNTs catalyst is only 14.5%. The chemical oxygen demand (COD) removal rates in 120 min for Cu0.075Mn0.075Fe2.85O4/MWCNTs and Fe3O4/MWCNTs catalysts are 82.7% and 67.3%, respectively. Furthermore, the p-NP conversion and COD removal rates of Cu0.075Mn0.075Fe2.85O4/MWCNTs nanocomposite still keep at 94.4% and 70.3% after five-time reuse, respectively. This catalyst shows good reusability for p-NP degradation and is very easy to recover from the treated water.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Manivannan Kokarneswaran ◽  
Prakash Selvaraj ◽  
Thennarasan Ashokan ◽  
Suresh Perumal ◽  
Pathikumar Sellappan ◽  
...  

AbstractUnique black coatings were observed in the inner wall of pottery shreds excavated from Keeladi, Tamilnadu, India. Raman spectroscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy were used to understand the nature of the coating. The analysis revealed the presence of single, multi-walled carbon nanotubes and layered sheets in the coating. The average diameter of single-walled carbon nanotube found to be about 0.6 ± 0.05 nm. This is the lowest among the single-walled carbon nanotubes reported from artefacts so far and close to the theoretically predicted value (0.4 nm). These nanomaterials were coated in the pottery’s that date backs to sixth century BC, and still retain its stability and adhesion. The findings of nano materials in the pre-historic artifacts, its significance and impact are discussed in this article.


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