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Quantum Dots as Biointeractive and Non-Agglomerated Nanoscale Fillers for Dental Resins
Published in Mary Anne S. Melo, Designing Bioactive Polymeric Materials for Restorative Dentistry, 2020
Isadora Martini Garcia, Fabrício Mezzomo Collares
In the nanometric scale, materials have different properties in comparison to their bulk state, leading to wide-ranging applications (Roduner 2006). Roduner (2006) made an interesting analogy to introduce this theme in his previous review: we have already accepted that some materials can present different allotropic forms and, consequently, show entirely different chemical and physical properties, as occurs with carbon. Similarly, materials’ properties depend on their size.
Treatment of skin with antioxidants
Published in Roger L. McMullen, Antioxidants and the Skin, 2018
Fullerenes represent one type of allotrope of carbon. Allotrope refers to possible crystalline forms of a molecule. For example, allotropes of carbon consist of diamond, fullerenes, and graphite. The most common form of fullerene is a C60 molecule containing a hollow molecular sphere that is characterized by its highly conjugated structure consisting of 30 carbon double bonds (Figure 8.27). Fullerenes were discovered in 1985 by researchers at Rice University in Houston, TX (United States), who later won the Nobel Prize in Chemistry.233The fullerenes became known as Buckminster Fullerenes, or Buckyballs, and received their name due to their structural resemblance to a geodesic sphere, specifically the Montréal Biosphère, which was designed by the American Architect, Buckminster Fuller.
Hyperthermia in oncology and nontoxic integrative treatments
Published in Clifford L. K. Pang, Kaiman Lee, Hyperthermia in Oncology, 2015
Clifford L. K. Pang, Kaiman Lee
Arsenic is an active and widespread heavy metal, with the atomic number 33. In the chemical elements, arsenic is a protean toxic element. Sometimes it seems to occur in the nonmetallic form; this characteristic is called allotropic form. It is usually known from the poison “white arsenic,” with the chemical name of arsenic trioxide. Toxicity of arsenic manifests in many ways; it has contact toxicity, causing inflammation and necrosis of the mucous membranes of the skin, and mostly it causes damages to the viscera, such as heart, liver, kidney, bone marrow, and brain. The human body has no detoxification function for arsenic, which can cause acute and chronic poisoning. Insurmountable environmental pollution provides a good opportunity for the toxicity of arsenic to spread, and consequently the contamination of drinking water has become a serious global problem. Studies show that incidences of cancer, especially gastrointestinal cancer, are significantly increased after the arsenic poisoning of large populations.
Recent advances in delivering RNA-based therapeutics to mitochondria
Published in Expert Opinion on Biological Therapy, 2022
Yuma Yamada, Sen Ishizuka, Manae Arai, Minako Maruyama, Hideyoshi Harashima
Mitochondria-targeted gene therapy requires the delivery of therapeutic molecules, such as RNA, into the mitochondria of target cells. There are two methods available for accomplishing this: allotopic expression and direct mitochondrial transfection. As summarized in this review, there appear to be only a few reports dealing with the latter. It is not a matter of which method is better, but of promoting research and development for each method so that either one can be used when necessary. In the development of vaccines against rapidly spreading unknown diseases such as SARS-CoV-2 infections, two useful tools could be available, namely, a viral vector and a non-viral vector, which are major driving forces in the development of these vaccines. In view of this, we conclude that it is important to develop allotropic expression systems of mitochondrial genes, direct mitochondrial transfection technology and different types of innovative methods for the development of mitochondrial innovative medicines. Preparation is the first step to success.
Peptides, proteins and nanotechnology: a promising synergy for breast cancer targeting and treatment
Published in Expert Opinion on Drug Delivery, 2020
Anabel Sorolla, Maria Alba Sorolla, Edina Wang, Valentín Ceña
This group includes the allotropic forms of carbon: fullerenes (cage-shaped), nanodiamonds, carbon nanotubes, graphene oxide and graphene quantum dots, widely used for biomedical applications [40]. Some of the advantages of carbon-based nanomaterials are their biocompatibility and interesting optical, mechanical, electrical and physicochemical properties. They are very stable, easy to be functionalized due to their high surface area, particularly for graphene, possess high penetration through biological membranes due to their shape, good scaffolds for drugs, fluorophores and radionuclides and excellent tight controllers of drug release [41]. However, due to their high stability in vivo and low solubility in aqueous media, carbon-based nanomaterials can induce toxicity but these handicaps can be addressed by further functionalization [41]. Currently, there are no carbon-based nanomaterials approved by regulatory agencies for BC treatment. However, there is a considerable amount of research demonstrating the utility of carbon-based nanomaterials in BC as controlled drug delivery agents, contrast agents, biosensors and therapeutics inducing photothermal effects. For example, graphene oxide NPs targeted with transferrin have shown high loading capacity of docetaxel (37%) which was released in a pH-dependent and sustainable manner in physiological conditions, inducing high toxicity in MCF-7 cells [42]. Also, graphene nanodots successfully killed MDA-MB-231 cells and xenografts by thermal ablation and allowed deep cancerous tissue imaging when using 670 nm laser irradiation [43].
Functional graphene oxide as cancer-targeted drug delivery system to selectively induce oesophageal cancer cell apoptosis
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2018
Jin-Huan Jiang, Jiang Pi, Hua Jin, Ji-Ye Cai
Graphene is a flat monolayer of carbon atoms tightly packed into a two-dimensional honeycomb structure. It is the basic structural element of other allotropes, including graphite, charcoal, carbon nanotubes and so on [1,2]. Due to its ultrahigh surface area and easy surface functionalization, graphene has been intensively explored for drug and gene delivery [3]. Graphene oxide (GO), as a derivate of graphene, possess advantageous biocompatibility, large specific surface area, large π-conjugated structures, and a lot of functional groups on its surface, which makes it easy to be functionalized and conferred excellent water solubility, physiological stability and capacity for drug delivery [4–6]. Therefore, most of studies with GO have focussed on the delivery of anticancer drugs in vitro [6–9].