scholarly journals Biological Activities of Carbon Nanotubes

10.5772/34916 ◽  
2012 ◽  
Author(s):  
Anurag Mishra ◽  
Yon Rojanasakul ◽  
Liying Wang
2019 ◽  
Vol 16 (4) ◽  
pp. 0878 ◽  
Author(s):  
Alwindawi Et al.

Carbon nanotubes (CNTs) were synthesized via liquefied petroleum gas (LPG) as precursor using flame fragments deposition (FFD) technique. In vitro, biological activates of carbon nanotubes (CNTs) synthesized by FFD technique were investigated. The physiochemical characterizations of synthesized CNTs are similar to other synthesized CNTs and to the standard sample. Pharmaceutical application of synthesized CNTs was studied via conjugation and adsorption with different types of medicines as promote groups. The conjugation of CNTs was performed by adsorption the drugs such as sulfamethoxazole (SMX) and trimethoprim (TMP) on CNTs depending on physical properties of both bonded parts. The synthesized CNTs almost have the same performance in antibiotic activity compared with standard sample of CNTs (commercial CNTs).The products were effective antibiotic in the treatment as resistant bacteria, may higher concentration of CNTs would have antibacterial activity on multi-drug resistant bacteria such as Acinetobacter and also on resistant E.coli. The bioactivity synthesized and standard samples of CNTs were almost the same against different types of bacteria.


Author(s):  
Jun Jiao

HREM studies of the carbonaceous material deposited on the cathode of a Huffman-Krätschmer arc reactor have shown a rich variety of multiple-walled nano-clusters of different shapes and forms. The preparation of the samples, as well as the variety of cluster shapes, including triangular, rhombohedral and pentagonal projections, are described elsewhere.The close registry imposed on the nanotubes, focuses attention on the cluster growth mechanism. The strict parallelism in the graphitic separation of the tube walls is maintained through changes of form and size, often leading to 180° turns, and accommodating neighboring clusters and defects. Iijima et. al. have proposed a growth scheme in terms of pentagonal and heptagonal defects and their combinations in a hexagonal graphitic matrix, the first bending the surface inward, and the second outward. We report here HREM observations that support Iijima’s suggestions, and add some new features that refine the interpretation of the growth mechanism. The structural elements of our observations are briefly summarized in the following four micrographs, taken in a Hitachi H-8100 TEM operating at an accelerating voltage of 200 kV and with a point-to-point resolution of 0.20 nm.


2017 ◽  
Vol 87 (3-4) ◽  
pp. 191-200 ◽  
Author(s):  
Nidhal Soualeh ◽  
Aliçia Stiévenard ◽  
Elie Baudelaire ◽  
Rachid Soulimani ◽  
Jaouad Bouayed

Abstract. In this study, cytoprotective and antioxidant activities of Rosa canina (RC) and Salix alba (SA), medicinal plants, were studied on mouse primary splenocytes by comparing Controlled Differential Sieving process (CDSp), which is a novel green solvent-free process, versus a conventional technique, employing hydroethanolic extraction (HEE). Thus, preventive antioxidant activity of three plant powders of homogeneous particle sizes, 50–100 µm, 100–180 µm and 180–315 µm, dissolved directly in the cellular buffer, were compared to those of hydroethanolic (HE) extract, at 2 concentrations (250 and 500 µg/mL) in H2O2-treated spleen cells. Overall, compared to HE extract, the superfine powders, i. e., fractions < 180 µm, at the lowest concentration, resulted in greater reactive oxygen species (ROS) elimination, increased glutathione peroxidase (GPx) activity and lower malondialdehyde (MDA) production. Better antioxidant and preventive effects in pre-treated cells were found with the superfine powders for SA (i. e., 50–100 µm and 100–180 µm, both p < 0.001), and with the intermediate powder for RC (i. e., 100–180 µm, p < 0.05) versus HE extract. The activity levels of catalase (CAT) and superoxide dismutase (SOD) in pretreated splenocytes exposed to H2O2, albeit reduced, were near to those in unexposed cells, suggesting that pretreatment with the fine powders has relatively restored the normal levels of antioxidant-related enzymes. These findings supported that CDSp improved the biological activities of plants, avoiding the use of organic solvents and thus it could be a good alternative to conventional extraction techniques.


Nature China ◽  
2007 ◽  
Author(s):  
Rachel Pei Chin Won
Keyword(s):  

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