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Photocatalytic Inactivation of Pathogenic Viruses Using Metal Oxide and Carbon-Based Nanoparticles
Published in Devarajan Thangadurai, Saher Islam, Charles Oluwaseun Adetunji, Viral and Antiviral Nanomaterials, 2022
Lan Ching Sim, Wei Qing Wee, Shien Yoong Siow, Kah Hon Leong, Jit Jang Ng, Pichiah Saravanan
Carbon nanotubes (CNTs) are a hollow cylindrical structure made of carbon. They are often synthesised by winding single layers or multiple layers of graphene sheets. Based on the number of layers wound, CNTs are classified into two categories: single-walled (SW) CNTs, which use single layers of graphene sheets, and multi-walled (MW) CNTs, which use more than one layer of graphene sheets. CNTs have the unique properties among other carbon nanoparticles to transport drugs or biomolecules to various types of targeted cells, such as cancer cells and T cells (Date and Destache 2013). Due to the conjugation and complexation of CNTs, it is possible to insert more than one type of functional group to the surface of CNTs. In theory, it is also possible to transport molecules through the internal cavity of CNTs (Bianco 2004). Pristine CNTs are known to be harmful to cell due to its properties of hydrophobicity and tendency to aggregate due to strong van der Waals force (Zhou et al. 2017). Methods have been studied to reduce the cytotoxicity by reducing the length of CNTs, such as introducing hydrophilic groups to the surface of CNTs to allow ease of transport through body and introducing structural defects to allow degradation by oxidative enzyme (Russier et al. 2011).
siRNA Delivery for Therapeutic Applications Using Nanoparticles
Published in Yashwant Pathak, Gene Delivery, 2022
These are synthesized from allotropes of carbon such as graphene, graphene oxide (GO), nanotubes, and fullerene. Studies show that carbon nanotubes complex with PEI and pyridinium exhibits 10–30% of silencing efficiency and 10–60% of cytotoxicity of siRNA. Studies have shown that carbon nanotube adjunct with PLL and Arg-Gly-Asp-Ser oligonucleotides actively target the tumors and control release of VEGF-siRNA, reducing the toxicity effect. These are hollow one-dimension nanostructures can be cylindrical, tubular, or needle in shape. Three types of Carbon nanotubes are discovered: single-walled carbon nanotubes with a thickness of 0.4–1 nm, double-walled carbon nanotubes with thickness of 1.4–20 nm, and multi-walled carbon nanotubes with a thickness of 20–100 nm [23].
Green Synthesis of Nanoparticles and Their Antimicrobial Efficacy against Drug-Resistant Staphylococcus aureus
Published in Richard L. K. Glover, Daniel Nyanganyura, Rofhiwa Bridget Mulaudzi, Maluta Steven Mufamadi, Green Synthesis in Nanomedicine and Human Health, 2021
Nonhlanhla Tlotleng, Marian Jiya John, Dumisile W. Nyembe, Wells Utembe
Carbon nanotubes are usually prepared using energy-intensive and environment-unfriendly methods such as laser vaporization, arc discharge, pyrolysis and chemical vapour deposition (CVD). However, in a recent study, Tripathi et al. (2017) utilized a plant-derived catalyst to synthesize MWCNTs. The notable results obtained were that the green catalyst synthesized CNT yield was much higher than that of metal catalyst grown CNTs. Moreover, the temperature used for the green catalyst grown CNTs was much less, i.e. 575°C, whilst that of metal catalyst grown CNTs range 700–1200°C (Tripathi et al., 2017).
Evaluation of toxicity of halloysite nanotubes and multi-walled carbon nanotubes to endothelial cells in vitro and blood vessels in vivo
Published in Nanotoxicology, 2020
Bihan Wu, Mengdie Jiang, Xuewu Liu, Chaobo Huang, Zhipeng Gu, Yi Cao
Thanks to their unique physicochemical properties, nanomaterials (NMs) with tubular structures have shown great potential in biomedical applications. One of the most extensively studied examples is probably carbon nanotubes (CNTs), which have been explored as promising nanoplatform for drug/gene delivery (Mohajeri, Behnam, and Sahebkar 2018) and bio-imaging (Teradal and Jelinek 2017). However, exposure to high levels of CNTs could induce adverse health effects, such as progression of atherosclerosis (Cao and Luo 2019; Moller et al. 2016), pulmonary fibrosis (Dong and Ma 2016) and DNA damage (Moller and Jacobsen 2017). For this consideration, the clinical progression of CNTs is relatively slow, and other NMs with tubular structures have gained extensive interest by researchers. Halloysite NTs (HNTs) are natural clay NTs with potential biomedical uses, such as drug delivery (Fizir et al. 2018), tissue engineering (Santos et al. 2018) and cancer cell labeling (Liu et al. 2019). Although HNTs have been considered as biocompatible materials, recent studies observed adverse health effects associated with HNT-exposure both in vivo and in vitro (Lai et al. 2013; Rong et al. 2019; Wang, Gong, et al. 2018), suggesting that the potential toxicity and the mechanisms of HNTs should be further investigated.
An evaluation of liposome-based diagnostics of pulmonary and extrapulmonary tuberculosis
Published in Expert Review of Molecular Diagnostics, 2020
Nikunj Tandel, Anish Z Joseph, Aishwarya Joshi, Priya Shrama, Ravi PN Mishra, Rajeev K. Tyagi, Prakash S Bisen
Nanotubes, nanobots, nanowires, and quantum dots are nanostructures besides nanoparticles that are coming into play in the area of molecular diagnostics [27]. Nanotubes are cylindrical carbon molecules generally measuring 0.5–3.0 nm in diameter, 20–1000 nm in length. Their peculiar attributes such as extraordinary strength and high conductance of electricity and thermal energy render high utility in the field of biomedical nanotechnology. Carbon nanotubes have been implicated in combination with other gold nanoparticles and silicon nanowires for the detection of oral cancer and lung cancer [28]. Nanocrystals, on the other hand, measure not more than 1 micron, at least by one dimension. The electrical and thermodynamic properties of these crystalline nanostructures vary with their size; however, nanocrystals falling in the range of 2 nm to 9.5 nm have been implicated in improving the solubility of certain drugs [29]. Nanowires are composed of carbon nanotubes or silicon. Antibodies that can be loaded over the surface can act as detectors. When the antibody binds to target biomolecules, specific conformational changes occur which can be recognized as signals. When several nanowires are loaded with different antibodies over the surface assembled in a single device, they can work as detectors for a disease, as used in cancer [28,30].
A short review on chemical properties, stability and nano-technological advances for curcumin delivery
Published in Expert Opinion on Drug Delivery, 2020
A nanotube is a tubular structure made up of hexagonal carbon-based networks (1–100 nm length). These networks have the arrangement of graphite sheets that are rolled up into a cylindrical configuration [32–35]. Common configurations of carbon nanotubes are the single-walled nanotubes (SWNTs), multiple-walled nanotubes (MWNTs) and C60 fullerenes. Due to their attractive size, geometrical and surface properties, carbon nanotubes are remarkable drug carriers. SWNT and C60 fullerenes are of 1 to 2 nm diameter while MWNT have up to 10 nm diameter. Carbon nanotubes and fullerenes have shown a great potential in tissue-specific delivery of drugs either through endocytosis or direct membrane insertion. Several experiments showed that fullerenes exert antioxidant and antitumor activities [125].