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Introduction to Nanomaterials for Drug Delivery
Published in Yasser Shahzad, Syed A.A. Rizvi, Abid Mehmood Yousaf, Talib Hussain, Drug Delivery Using Nanomaterials, 2022
Akhlesh Kumar Jain, Keerti Mishra
Gold nanoparticles consist of a small gold particle with a diameter of 1 to 100 nm with or without surface decorated ligands (Figure 1.3) (Chen et al., 2014). It is very easy to synthesize gold nanoparticles of dissimilar morphology, such as into spheres, rods, cages, or stars, which enables the gold nanoparticles to attain anticipated characteristics like increased solubility in water, enhanced size dispersion, and other desired surface functionalities. Gold nanoparticles have excellent biocompatibility and are nontoxic. The size and shape of these nanoparticles are easy to modify; thus, it becomes easy to manage to their conjugating and optical properties, due to which they have received special attention. Further, it is well known that gold is oxidation resistant under physiological conditions that allow an unrestricted interaction of gold with the biological environment. In the gene therapy and imaging, DNA or drug delivery is achieved through gold NPs (Huang et al., 2007; Peng et al., 2009; Santos et al., 2018; Wei et al., 2007).
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Published in Valerio Voliani, Nanomaterials and Neoplasms, 2021
Alaaldin M. Alkilany, Catherine J. Murphy
Gold nanoparticles have attracted enormous scientific and technological interest due to their ease of synthesis, chemical stability, and unique optical properties. Proof-of-concept studies demonstrate their biomedical applications in chemical sensing, biological imaging, drug delivery, and cancer treatment. Knowledge about their potential toxicity and health impact is essential before these nanomaterials can be used in real clinical settings. Furthermore, the underlying interactions of these nanomaterials with physiological fluids is a key feature of understanding their biological impact, and these interactions can perhaps be exploited to mitigate unwanted toxic effects. In this Perspective we discuss recent results that address the toxicity of gold nanoparticles both in vitro and in vivo, and we provide some experimental recommendations for future research at the interface of nanotechnology and biological systems.
Intelligent Nanomaterials for Medicine: Carrier Platforms and Targeting Strategies—State of the Art
Published in Lajos P. Balogh, Nano-Enabled Medical Applications, 2020
Georgette B. Salieb-Beugelaar, Marc Wolf, Roman Lehner, Kegang Liu, Stephan Marsch, Patrick Hunziker
Metallic nanoparticles such as iron oxide, gold, and silver have been developed and modified for use in drug delivery, magnetic separation, and diagnostic imaging [87–90]. Superparamagnetic nanoparticles (SPION) built from oxide nanoparticles, such as magnetite (Fe3O4) and maghemite (Fe2O3), exhibit particular features like ultrafine size, biocompatibility, and magnetic properties. The superparamagnetic properties become manifest when a magnetic moment is induced through the application of a magnetic field. The large magnetic moment yields a strong signal change in magnetic resonance imaging (MRI) allowing therefore sensitive detection at high resolution [91]. Another application of iron oxide nanoparticles is tumor treatment by magnetically induced hyperthermia [92]. Thanks to its chemical inertness and suited mechanical properties, gold has been used in medicine for teeth implants and is also in use in cancer radiotherapy [93]. Gold nanoparticles can be formed with core sizes ranging from 1 to 100 nm. The initial claim of absence of cytotoxicity has raised enthusiasm as an excellent drug delivery system although increasing recognition of size dependent cytotoxicity needs to be considered before their application [94, 95]. Gold nanoparticles are capable of delivering peptides, proteins nucleic acids, or small molecules. When functionalized with quaternary ammonium groups, they can bind negatively charged DNA or RNA and also protect the nucleic acids from enzymatic degradation [96].
Viburnum opulus fruit extract-capped gold nanoparticles attenuated oxidative stress and acute inflammation in carrageenan-induced paw edema model
Published in Green Chemistry Letters and Reviews, 2022
Cristina Bidian, Gabriela Adriana Filip, Luminița David, Bianca Moldovan, Ioana Baldea, Diana Olteanu, Mara Filip, Pompei Bolfa, Monica Potara, Alina Mihaela Toader, Simona Clichici
AuNPs were obtained by a green procedure that involves the reduction of Au3+ ions using the antioxidant phytocompounds of VO fruits. To this end, at 25 mL diluted fruit extract 100 mL of boiling 1 mM HAuCl4 solution were added and the resulting mixture was stirred for 1 h. The progress of the reduction reaction was visually and spectrophotometrically evaluated using a Perkin-Elmer Lambda 25 UV-Vis double-beam spectrophotometer. The color change from faint red to intense purple indicates the formation of a colloidal gold solution. The AuNPs were purified by repeated centrifugation at 10.000 rpm and washed. Several consecrated methods have been used to evaluate the properties of the synthesized gold nanoparticles, including UV-Vis spectroscopy, transmission electron microscopy (TEM), dynamic light scattering (DLS) and zeta potential. An H-7650 120 kV automatic TEM Hitachi microscope on a carbon-coated copper greed was used to investigate the size and morphology of the AuNPs, and the hydrodynamic diameter and zeta potential were determined using a Zetasizer Nano ZS-90 instrument (Malvern Instruments Ltd., Malvern, UK) equipped with a He–Ne laser.
Gold nanoparticles: synthesis, application in colon cancer therapy and new approaches - review
Published in Green Chemistry Letters and Reviews, 2021
Karen Magaly Soto, Sandra Mendoza, Jose M. López-Romero, Jose Ramón Gasca-Tirado, Alejandro Manzano-Ramírez
In the past years, gold was used only as a metal for the fabrication of jewelry and utensils; however, with advances in nanotechnology, its physicochemical properties have been studied, making it an ideal material for nanoparticle manufacture. Gold nanoparticles, also called gold colloids, usually have a size between 1 and 100 nm, exist in different morphology types, including nanospheres, nanorods, nanoshells, and nanocages (20). They are the most stable metal nanoparticles and display unique properties (depends on their size, shape, hollowness/porosity, and other properties) not found in bulk-size materials. They are preferred over other metal nanoparticles because they have different advantages, such as easy synthesis. The shape and size may be controlled by experimental parameters, present a large surface-to-volume ratio, possess unique optical properties, and exhibit excellent compatibility with almost chemically and biological molecules (21,22). Some examples of the applications of gold nanoparticles are sensors (23), diagnostics (24), therapeutic agents (25), catalysis (26), photodynamic therapy (27), and enzymatic assays (28).
Optical concentration of gold nanoparticles as a new concept of analytical sensitivity
Published in Instrumentation Science & Technology, 2021
Samira Vaziri Heshi, Nader Shokoufi, Seyed Nader Seyed Reihani
Gold nanoparticles exhibit unique optical properties that depend on their size, shape, and morphology. They exhibit different colors in a shape-size-dependent manner.[14] Compared to other types, gold nanoparticles have several advantages including controllable synthesis,[15] easy surface modification,[16] and high molar absorption coefficients, making them ideal nanoprobes for sensing.[17,18] It is very critical to know the number of the gold nanoparticles in a sample in order to understand their biological and environmental effects. This requires analytical methods that focus on the number of particles in a sample. Therefore, new instruments or new protocols for existing instruments are required to quantitatively determine the number of nanoparticles.