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Application of Nanotechnology in Drug Delivery
Published in Khalid Rehman Hakeem, Majid Kamli, Jamal S. M. Sabir, Hesham F. Alharby, Diverse Applications of Nanotechnology in the Biological Sciences, 2022
Muzafar Ahmad Rather, Showkeen Muzamil Bashir, Showkat Ul Nabi, Salahi Uddin Ahmad, Jiyu Zhang, Minakshi Prasad
Nanoclusters signify a bunch of self-assembled nanoparticles with at least one dimension and size distribution in nanoscale range. The composition is either the single atom of an element or collection of atoms of different elements in stoichiometric ratios. These atoms are linked with each other by ionic, covalent, metallic, hydrogen bonds or by van der Waals forces (Sinha et al., 2017). Precious metal nanoclusters (typically in the size range from 1 to 3 nm and containing ~ 10 to ~1000 metal atoms) represent a bridge state between small molecules (<~1 nm) and metal nanoparticles (>~3 nm) (Fornasiero and Cargnello, 2017). Bulk materials have constant physical properties whereas the physical properties of nanoclusters depend on their size (Sinha et al., 2017). The properties of nanoclusters are particularly interesting and have gained much scientific attention due to their unique physical and chemical properties that depend on size, shape, composition, and environment and influence properties of the cluster. With their size approaching the Fermi wavelength of electrons, metal NCs possess molecule-like properties and excellent fluorescence emission. Owing to their ultrasmall size, strong fluorescence, and excellent biocompatibility, they have been widely studied in environmental and biological fields concerning their applications. The fluorescence properties of nanoclusters (such as silver, gold, or magnetic particles) owing to their molecular-like size have been applied in biomedical applications for biosensing and bio-imaging and also to drug delivery.
Recent Developments in Nanoparticulate-Mediated Drug Delivery in Therapeutic Approaches
Published in Jyoti Ranjan Rout, Rout George Kerry, Abinash Dutta, Biotechnological Advances for Microbiology, Molecular Biology, and Nanotechnology, 2022
Janmejaya Bag, Swetapadma Sahu, Monalisa Mishra
Nanoclusters are the self-assembled NPs formed of either polymers or organic molecules of smaller size. These polymers are cross-linked with the silver, gold, or magnetic particles (Diez and Ras, 2011; Xie et al., 2009; Ditsch et al., 2005) (Figure 18.5). Nanoclusters show both molecular and fluorescence properties, which makes them a perfect carrier for drug delivery, bioimaging, and biosensing.
Synthesis and Structure of Selenolate-Protected Metal Nanoclusters
Published in Yan Zhu, Rongchao Jin, Atomically Precise Nanoclusters, 2021
Owing to their ultrasmall size (<2 nm), metal nanoclusters exhibit strong quantum size effects, which endow them with unique physicochemical properties [1–5], such as multiple absorption bands [6], strong photoluminescence [7, 8], magnetism [9], and outstanding catalytic reactivity [10–12], which are different from those of the large nanoparticles with surface plasmon resonance (SPR). Metal nanoclusters have attracted wide interest since they have a significant potential application as functional materials. Among these metal nanoclusters, ligand-protected metal nanoclusters are most widely studied, and they are generally composed of metal kernels and surface protecting ligands [4, 5, 13–16]. It is known that metal kernels show high chemical and physical activities [17, 18], and the physicochemical properties of metal nanoclusters highly depend on the size, composition, and atom-packing mode of the metal kernel [19–21]. So, the kernel of metal nanoclusters has received relatively more attention.
A comparative DFT study of structural, electronic, thermodynamic, optical, and magnetic properties of TM (Ir, Pt, and Au) doped in small Tin (Sn5 & Sn6) clusters
Published in Phase Transitions, 2022
Aoly Ur Rahman, Dewan Mohammad Saaduzzaman, Syed Mahedi Hasan, Md. Kabir Uddin Sikder
The study of nanoclusters that contain several constituent particles ranging from ∼10 to 106 has become very important for promising technological applications such as in semiconductor and nanodevice development. Nanocluster study is also necessary to understand their size-dependent various properties along with geometrical and physiochemical structures [1–9]. Also, the advancement of the application of semiconductors in digital electronics devices and nano-engineering, the semiconducting properties of the elements from IVA have gained enormous attention from researchers [10–18]. During the last few decades, a great number of theoretical and experimental studies have been performed to investigate the geometric, electronic, thermodynamic, and magnetic properties of Tin (Sn), the fourth element of IVA, and their small clusters [19–22]. Characteristically, Tin (Sn) nanoclusters were found as metallic tetragonal β-phase at ambient temperature. However, at lower temperatures, pure Sn-nanoclusters can be found in α-phase with diamond lattice structure of lower energy bandgap [7].
New perspectives on the nature and imaging of active site in small metallic particles: II. Electronic effects
Published in Chemical Engineering Communications, 2021
It is appropriate here (for clarity) to also make a distinction between the several somewhat equivalent (but different) terms used in the definitions of nanostructured materials, especially important from the standpoint of overall geometry: Nanoparticle, nanocluster, nanocrystal, or nanoensemble (with or without the prefix, nano). The first term is the most common; it refers to a nanomaterial with some shape/morphology at the nanoscale, upto about 5–10 nm in size (catalytically most relevant), with a specific particle size distribution. The term, “nanocluster,” is a more specific term, and though initially reserved for size-selective nanoclusters, it can now include any small particle, upto 10 nm in diameter. In this sense, the terms “nanoparticle” and “nanocluster” are used interchangeably, without any apparent distinction. The term, “nanocrystal” can also imply any type of nanoparticle, but of a specific surface shape (such as a cube, spherical or quasi-spherical, rods, any polygon such as cuboctahedral, cuborhombohedral, and even wires). It is interesting to note that while the terms crystallite and crystal are frequently used to refer metallic nanoparticles, it is more appropriate to use these for supports or carriers, as the supports have a definitive crystal structure and geometry. The metallic nanoparticles are of a quasi-equilibrium character, usually with significant lattice strain, and not perfectly crystalline.
New perspectives on the nature and imaging of active site in small metallic particles: I. Geometric effects
Published in Chemical Engineering Communications, 2021
At the outset, it is appropriate to make a distinction between the several somewhat equivalent (but different) terms used in the definitions of nanostructured materials, especially important from the standpoint of overall geometry – which is the theme of this presentation: Nanoparticle, nanocluster, nanocrystal, or nanoensemble (with or without the prefix, nano). The first term is the most common; it refers to a nanomaterial with some shape/morphology at the nanoscale, upto about 5–10 nm in size (catalytically most relevant), with a specific particle size distribution. The term, “nanocluster,” is a more specific term, and though initially reserved for size-selective nanoclusters, it can now include any small particle, upto 10 nm in diameter. In this sense, the terms “nanoparticle” and “nanocluster” are used interchangeably, without any apparent distinction. The term, “nanocrystal” can also imply any type of nanoparticle, but of a specific surface shape (such as a cube, spherical or quasi-spherical, rods, any polygon such as cubo-octahedral, cubo-rhombohedral, and even wires). It is interesting to note that while the terms crystallite and crystal are frequently used to refer metallic nanoparticles, it is more appropriate to use these for supports or carriers, as the supports have a definitive crystal structure and geometry. The metallic nanoparticles are of a quasi-equilibrium character, usually with lattice strain, and not perfectly crystalline.