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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].
An Insight into Advanced Nanoparticles as Multifunctional Biomimetic Systems in Tissue Engineering
Published in Harishkumar Madhyastha, Durgesh Nandini Chauhan, Nanopharmaceuticals in Regenerative Medicine, 2022
Kusha Sharma, Abhay Tharmatt, Pooja A Chawla, Kamal Shah, Viney Chawla, Bharti Sapra, Neena Bedi
In an investigation, a UV-cross-linkable gold (GNR)-incorporated gelatin methacrylate (GelMA) hybrid was fabricated for its utilisation in cardiac TE (Cromer Berman et al., 2011). The incorporated nanomaterial was reported to promote the hydrogel matrix’s mechanical stiffness and electrical conductivity, and the hybrid hydrogels seeded cardiomyocytes represented excellent viability, cell retention, and metabolic activity. Similarly, carbon-based nanomaterials, such as carbon nanotubes (CNTs), have enhanced conductivity-related characteristics. For instance, a study reported the synthesis of cardiac patches by planting neonatal rat cardiomyocytes onto CNT-incorporated photo-cross-linkable gelatin methacrylate hydrogels. The electrically conductive and nanofibrous complexes formed by CNT were reported to improve cardiac cell adhesion and organisation and provide outstanding mechanical integrity and improved electrophysiological functions.
Comparative assessments of the biodistribution and toxicity of oxidized single-walled carbon nanotubes dispersed with two different reagents after intravenous injection
Published in Nanotoxicology, 2021
Minfang Zhang, Ying Xu, Mei Yang, Masako Yudasaka, Toshiya Okazaki
Owing to their outstanding physical and chemical properties, carbon nanotubes (CNTs) [Iijima 1991; Iijima and Ichihashi 1993] have been tested in various applications in the fields of electronics, composite materials, and energy, as well as in biological fields such as therapeutics and imaging applications [De Volder et al. 2013; Baughman, Zakhidov, and de Heer 2002; Tan et al. 2012; Liu et al. 2009; Martincic and Tobias 2015]. The distinctive chemical and physical characteristics of CNTs are dependent on their extremely small sizes and fiber-like shapes. CNTs may be potentially hazardous to humans, with public concerns about their possible environmental and toxicological effects increasing as the number of CNT products entering the market has increased. Several studies in animals found that a few types of multi-wall CNTs (MWNTs) were carcinogenic [Ryman-Rasmussen et al. 2009; Rittinghausen et al. 2014; Sakamoto et al. 2018; Kobayashi, Izumi, and Morimoto 2017; Poland et al. 2008; Takagi et al. 2008], leading the Swedish nonprofit organization ChemSec to add CNTs to the SIN (‘Substitute It Now’) list [Hansen and Lennquist 2020]. Moreover, the International Agency for Research on Cancer (IARC) has categorized the MWNTs MWNT-7/XNRI-7 to group 2B, indicating that they are possible carcinogens in humans. All other types of MWNTs, as well as single-wall CNTs (SWNTs), have not yet been classified due to limited toxicological research [IARC 2017]. Determining the possible toxicity of SWNTs requires more detailed investigations.
Functionalized carbon-based nanomaterials and quantum dots with antibacterial activity: a review
Published in Expert Review of Anti-infective Therapy, 2021
Mehran Alavi, Erfan Jabari, Esmaiel Jabbari
Carbon nanotube (CNT), a noteworthy one-dimensional NM, can be synthesized in single-wall CNT (SWCNT) and multi-wall CNT (MWCNT) forms by high-pressure carbon monoxide disproportionation (HPCO), chemical vapor deposition (CVD), laser ablation, and arc discharge. Unique properties, including excellent elastic modulus, tensile strength, electro-optical and thermal conductivity, were reported for these NMs [24]. Aspect ratio (AR) (the length-to-diameter ratio) is a determinant factor for the antibacterial value of CNTs. Effect of AR value on antibacterial properties is different when in solid state as opposed to a liquid medium is different. Self-aggregation of CNTs with higher AR in liquid medium resulted in more antibacterial activities compared to lower AR. In this regard, CNTs with higher AR have a larger surface to interact with more bacteria. In contrast, in solid state, CNTs with a lower AR can damage bacterial envelope through nanotube’s open-end. Modification of CNTs by several groups such as amine (–NH2) and antibacterial agents can increase antibacterial activities [25]. According to the above-mentioned introduction, the objective of this mini-review is to explain the recent advancements related to antimicrobial abilities of various modified CNT, graphene, graphene oxide, and carbon QDs (Table 1).
Exploring the effectiveness of incorporating carbon nanotubes into bioengineered scaffolds to improve cardiomyocyte function
Published in Expert Review of Clinical Pharmacology, 2020
Paridhi Ghai, Thomas Mayerhofer, Rajesh Kumar Jha
Primary articles were selected using the keywords listed above. Since this topic was not in clinical application stages, journal articles of preclinical experimental nature were sought as primary literature. Secondary literature included articles for background information. Studies that specifically addressed the impact of carbon-nanotube incorporation into scaffolds were sought, as there were many related studies that explored other aspects of carbon nanotubes effect on tissue engineering. Studies that purposely discussed cardiac tissue engineering were chosen, as many were focused on other permanent tissue such as neurons. Exclusion criteria were set as: reviews primary articles, studies pertaining to other permanent tissue, alternative aspects of carbon-nanotube effects on tissue, and applications of nanoengineering and robotics not pertaining to efficacy of carbon nanomaterials for enhancing scaffolds of engineered cardiac tissue.