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Nanocarriers as an Emerging Platform for Cancer Therapy
Published in Lajos P. Balogh, Nano-Enabled Medical Applications, 2020
Dan Peer, Jeffrey M. Karp, Seungpyo Hong, Omid C. Farokhzad, Rimona Margalit, Robert Langer
Nanoshells (100–200 nm) may use the same carrier for both imaging and therapy (Table 2.2). They are composed of a silica core and a metallic outer layer. Nanoshells have optical resonances that can be adjusted to absorb or scatter essentially anywhere in the electromagnetic spectrum, including the near infrared region (NIR, 820 nm, 4 W cm−2), where transmission of light through tissue is optimal. Absorbing nanoshells are suitable for hyperthermia-based therapeutics, where the nanoshells absorb radiation and heat up the surrounding cancer tissue. Scattering nanoshells, on the other hand, are desirable as contrast agents for imaging applications. Recently, a cancer therapy was developed based on absorption of NIR light by nanoshells, resulting in rapid localized heating to selectively kill tumours implanted in mice. Tissues heated above the thermal damage threshold displayed coagulation, cell shrinkage and loss of nuclear staining, which are indicators of irreversible thermal damage, whereas control tissues appeared undamaged [37, 89].
An Introduction to Specially Tailored Nanomaterials for Biomedical Applications
Published in Jince Thomas, Sabu Thomas, Nandakumar Kalarikkal, Jiya Jose, Nanoparticles in Polymer Systems for Biomedical Applications, 2019
Minu Elizabeth Thomas, K. P. Sajesha, P. M. Sayeesh, Jince Thomas
Nanoshells are a novel class of nanoparticles which are optically tunable. It consists of a core which is dielectric and a thin coating of metal shell around it. Nanoshell studies were started by Halas et al. Experimentally, first metal nanoshell was prepared by Zhou et al. using the present available techniques; there are many methods to synthesize the nanoshell. Most of them are single- and double-step synthesis. The uniform coating is the challenge that faces in the synthesis. Nanoshells can be synthesized using metal, semiconductors, and insulators. Dielectric materials can be used as core like silica and polystyrene; they are stable (Fig. 1.7). Depending on the core radius and thickness of shell, nanoshell can be designed to absorb or scatter light to a large range of spectra that can allow the maximum light penetration through the tissues. This property of nanoshells along with its chemical inertness and water solubility allows it to be used for diagnostic and therapeutic purposes. Oxide and metal nanoshells are the two different types of nanoshells. Metal nanoshells have notable application in the cancer treatment and bioimaging.
Nano-biotechnology
Published in Firdos Alam Khan, Biotechnology Fundamentals, 2018
Buckyballs may be used to trap free radicals generated during an allergic reaction and block the inflammation that results from an allergic reaction. Nanoshells may be used to concentrate the heat from infrared light to destroy cancer cells with minimal damage to surrounding healthy cells. Nanospectra Biosciences has developed such a treatment using nanoshells illuminated by an infrared laser, which has been approved for a pilot trial with human patients. Nanoparticles when activated by x-rays that generate electrons cause the destruction of cancer cells to which they attach. This is intended to be used in the place of radiation therapy, with much less damage to healthy tissue. Nanobiotix has released preclinical results for this technique. Aluminosilicate nanoparticles can more quickly reduce bleeding in trauma patients by absorbing water, causing blood in a wound to clot quickly. Z-Medica is producing medical gauze that uses aluminosilicate nanoparticles. Nanofibers can stimulate the production of cartilage in damaged joints. The list of companies that make nanotechnology healthcare products is given in Table 10.1.
Overview of the application of inorganic nanomaterials in breast cancer diagnosis
Published in Inorganic and Nano-Metal Chemistry, 2022
Asghar Ashrafi Hafez, Ahmad Salimi, Zhaleh Jamali, Mohammad Shabani, Hiva Sheikhghaderi
Typically, nanoshells are fabricated of dielectric silica nanoparticle core which was covered using a thin layer of metallic shells. In this type of nanomaterial, optical resonances were adjusted by the change of shells thickness and cores radius. Accordingly, nanoshells can have the adsorption/emission in the broad range of the wavelength like near infrared where tissue transmissivity is the highest due to low scattering and absorption from inherent chromophores. For instance, silica nanoparticle (SNP) as the core in nanoshells has exceptional properties, which has attracted much attention in medical applications. In other words, the most important properties of SNP are physicochemical, mechanical and optical properties. As the increase of optical properties of SNPs can be accessed with of the tine layer of noble metal on a surface of SNPs, therefore, optical properties of SNP have made it an interesting candidate in molecular imaging.[155–158]
Electrodeposition of Cu2O nanostructures with improved semiconductor properties
Published in Cogent Engineering, 2021
Andrés Boulett, Guadalupe Del C. Pizarro, Rudy Martin-Trasanco, Julio Sánchez, Federico Tasca, Omar E. Linarez Pérez, Alejandra Tello, Diego P. Oyarzún
By performing the electrodeposition in the presence of p(NVP-co-AI) copolymer at 0.1 %w/v (1:1), nanostructures were obtained along the surface of the ITO in the form of nanospheres, accompanied by nanosheets (Figure 3 “IA” and “IB”). In addition, a uniform morphology is observed with a higher concentration of nanospheres above the nanosheets, which are deposited at random on the surface of the substrate (see Figure 3 “ID”). By observing the SEM micrographs with the highest magnification, it was determined that the nanoshells tend to agglomerate with each other, while the nanoshells are deposited on the surface individually (Figure 3 “IC” and “ID”). Finally, it was determined that the average diameter of the nanoshells ranges from 78 nm to 91 nm (Figure 3 “IE” and “IF”).
Near-infrared light for on-demand drug delivery
Published in Journal of Biomaterials Science, Polymer Edition, 2018
Another material that has been widely studied for photothermal cancer therapy is gold, which is a unique plasmonic material with tunable optical properties (Figures 2 and 3). Gold nanorods have unique NIR absorption properties because of their aspect ratios. Huang et al. created gold nanorods conjugated with monoclonal anti-epidermal growth factor receptor (anti-EGFR) antibodies to specifically target malignant cells. Using a nonmalignant human keratinocyte HaCaT cell line and two malignant human oral squamous cells (carcinoma HOC 313 clone 8 and HSC 3), they confirmed selective hyperthermia in the malignant cells [26]. Because of the overexpression of EGFR on the cancer cells, the anti-EGFR antibody conjugated nanorods induced the death of these cells specifically, whereas the benign HaCaT cells required a far higher laser energy of 160 mW at 800 nm to elicit similar effects. Using local hyperthermia with gold nanoshells, Atkinson et al. demonstrated the reduction of radio-resistant breast tumors, which commonly cause the recurrence and metastasis of breast cancer [27]. The authors used human triple-negative breast cancer xenografts derived from mice that did not express the following markers: estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2. By treating radio-resistant breast cancer stem cells with NIR-illuminated gold nanoshells, it was demonstrated that the thermal treatment of NIR-associated gold nanoshells can be a clinically effective approach. Among the several gold nanostructures investigated for therapeutic purposes, gold nanocages have recently garnered attention, as they offer the unique properties of gold while simultaneously serving as reservoirs for holding therapeutics within their hollow structure [26]. These hollow gold nanocages can be fabricated through galvanic replacement reactions with HAuCl4 on silver nanocube templates [28]. The wall thickness and porosity of the gold nanocages, which are determined by the extent of the galvanic replacement reaction, can affect their surface plasmon resonance (SPR) properties. In one study, gold nanocages were coated with monolayered poly(ethylene glycol) (PEG) so that they could be retained within the tumor body via while maintaining enhanced permeability and retention without rapid clearance into the bloodstream [29]. For obtaining in vivo localized SPR with NIR at 808 nm, the PEGylated gold nanocages were tuned and injected into athymic mice bearing the U87MGwtEGFR human glioblastoma cell line. The authors confirmed an increase in temperature around the tumor tissues, which reduced the cell metabolism and cellular damage, resulting in the death of tumor cells.