Chemistry
Nanoparticles
Nanoparticles are tiny particles with dimensions on the nanometer scale, typically ranging from 1 to 100 nanometers. They can be made from various materials and are used in a wide range of applications, including drug delivery, electronics, and catalysis. Their small size gives them unique properties that differ from those of larger particles, making them valuable in many fields.
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10 Key excerpts on "Nanoparticles"
eBook - PDF- Jillian F. Banfield, Alexandra Navrotsky, Jillian F. Banfield, Alexandra Navrotsky(Authors)
- 2018(Publication Date)
- De Gruyter(Publisher)
1 Nanoparticles in the Environment Jillian F. Banfield* and Hengzhong Zhang Department of Geology and Geophysics University of Wisconsin-Madison 1215 West Dayton Street Madison, Wisconsin 53 706 * Current Address: Department of Earth and Planetary Science University of California-Berkeley Berkeley, California 94720 INTRODUCTION Nanoparticles are discrete nanometer (10 9 m)-scale assemblies of atoms. Thus, they have dimensions between those characteristic of ions (10 1CI m) and those of macroscopic materials. They are interesting because the number of atoms in the particles is small enough, and a large enough fraction of them are at, or near surfaces, to significantly modify the particle's atomic, electronic, and magnetic structures, physical and chemical properties, and reactivity relative to the bulk material. Nanoparticle surfaces themselves may be distinctive. Particles may be terminated by atomic planes or clusters that are not common, or not found, at surfaces of the bulk mineral. These, and other size-related effects will lead to modified phase stability and changes in reaction kinetics. What makes a nanoparticle a nanoparticle? Definitions of the size ranges for molecules, Nanoparticles, and macroscopic solids must be compound specific. However, a useful upper limit for Nanoparticles is the size at which one of its properties deviates from the value for the equivalent bulk material by an amount that is significantly larger than the error of the method used to make the measurement (a few percent). In practice, some characteristic will probably be different enough to warrant description as a nanoparticle if it is less than a few tens of nanometers in diameter, and perhaps less than a fraction of a micron in diameter. Because of the importance of size-dependent property changes to the materials sciences, size-property relationships have been studied in detail for some systems.
eBook - ePubCharacterization and Biology of Nanomaterials for Drug Delivery
Nanoscience and Nanotechnology in Drug Delivery
- Shyam Mohapatra, Shivendu Ranjan, Nandita Dasgupta, Sabu Thomas, Raghvendra Kumar Mishra, Shyam Mohapatra, Shivendu Ranjan, Nandita Dasgupta, Sabu Thomas, Raghvendra Kumar Mishra, Raghvendra Kumar(Authors)
- 2018(Publication Date)
- Elsevier(Publisher)
Chapter 12Design and Characterization of Nanoparticulate Drug Delivery
Basavaraj K. Nanjwade1, Arindam Basu Sarkar2, and Teerapol Srichana31 Trroy Life Sciences Pvt Ltd., Bengaluru, India2 University of Findlay, Findlay, OH, United States3 Prince of Songkla University, Hat-Yai, ThailandAbstract
Nanoparticles are currently generating great scientific interest as they act as a bridge between bulk substances and molecular structures lying underneath. Substances at the nano scale behave differently, mainly due to their large surface area and the quantum effect of the Nanoparticles. Nanosized particles exhibit different optical, mechanical, electromagnetic, and thermal properties in comparison with large-size particles. Localized surface plasmon resonance affects the optical property of the nanoparticle, so the gold nanoparticle has a wine-red color and silver exhibits a yellowish-grey color. Mechanical properties like hardness and strength of material increase with reducing structure of particle. Two-dimensional and three-dimensional images are observed to study the particle shape at nanosize. The density reference liquid method might be used for the measurement of individual density of Nanoparticles. The composite structure of Nanoparticles exhibited the increase in surface energy of particles, which results in enhanced cohesion of particles. In the evaluation of Nanoparticles, scanning electron microscopy, transmission electron microscopy, and sample preparation methods are studied.Keywords
Design; Drug; Nanomedicine; Nanoparticulate; Study1. Basic Concepts of Nano
The prefix “nano” means a billionth, derived from the Greek word “νᾶνος” meaning “dwarf.” One nanometer (nm) is equal to one-billionth of a meter, i.e., 1nm=10− 9m or one-millionth of 1mm or one-thousandth of 1μm. The size of a nanometer is enlightened by simple examples, such as a human hair is approximately 80,000nm wide and 50,000nm in diameter, and a typical blood cell is approximately 7000 nm wide and 2000nm in height. Fig. 12.1
eBook - ePubBiomaterials Science
An Introduction to Materials in Medicine
- Buddy D. Ratner, Allan S. Hoffman, Frederick J. Schoen, Jack E. Lemons(Authors)
- 2012(Publication Date)
- Academic Press(Publisher)
Chapter I.2.19
Microparticles and Nanoparticles
Shalu Suri1 , Gang Ruan2 , Jessica Winter2 and Christine E. Schmidt3 , ∗1 School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA, USA2 Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, OH, USA3 Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA.∗ Note: will have new address effective Jan. 1, 2013: J. Crayton Pruitt Family Department of Biomedical Engineering, Biomedical Sciences Building, Gainesville, FL, USAIntroduction
Microparticles and Nanoparticles have had an enormous impact on a wide-range of biomedical applications including drug delivery, imaging, and basic research. Miniaturization of therapeutic devices to the micron (1–1000 μm), sub-micron (100–1000 nm), and nanometer (1–100 nm) scales has facilitated the integration of biomedical devices with therapeutic biomolecules for improved clinical efficacy (George et al., 2005 ). Despite an extensive database on microparticles and Nanoparticles, a clear universal boundary between nano- and microsize does not exist in the literature. Expert opinions in the micro- and nano-sciences have emphasized that 1–100 nm is the optimum nanoscale range; however, in biotechnology and medicine, the definition of “nano” is less stringent (Ferrari, 2005 ). Design of any miniaturized system is dependent on the endpoint application. For example, systemic (intravascular) application requires use of particles less than 500 nm in diameter, whereas for intramuscular application or in some cases oral delivery applications, particles greater than 1 micron and less than 125 μm can be easily administered (Jain, 2000 ). Other than size, another critical parameter that can significantly modulate the function of these particles is shape (Champion et al., 2007 ); shape can impact cellular uptake by immune cells, release behavior of biomolecules, and cell targeting. A variety of materials have been synthesized as micro- and Nanoparticles, mostly for imaging or targeted delivery of therapeutic biomolecules such as hormones, vaccine antigens and adjuvants, peptides, and anti-inflammatory agents (Aukunuru et al., 2003 ; Kim et al., 2004 ). In addition, these particles have been used as biosensors and in affinity bioseparations, immunological assays, cell labeling, and cell sorting. Also see Chapters II.5.16.B1 to II.5.16.B9
eBook - PDFInorganic Micro- and Nanomaterials
Synthesis and Characterization
- Angela Dibenedetto, Michele Aresta, Angela Dibenedetto, Michele Aresta(Authors)
- 2013(Publication Date)
- De Gruyter(Publisher)
Nanoparticles may have various compositions, encompassing purely inorganic, hybrid inorganic-organic, and organic materials. Inorganic Nanoparticles owe their activity to the large number of atoms per unit surface. It is noteworthy that, although the definition of nanoparticle includes sizes from 1 to 100 nm, nevertheless the properties may con-siderably change with size as shown in Figure 8.2. Figure 8.2 shows that the number of atoms on the surface very rapidly increases in the range from 1–5 nm. The total interval can be quite correctly divided into 5 parts, identifying the ranges 1–5 nm, 6–15 nm, 16–30 nm, 31–50 nm, 51–100 nm as the regions with different properties and activity. Nanoparticles with a dimension smaller than 15 nm may have quite unique properties due to their particular thermodynamics [5]. Such Nanoparticles may be stabilized by changes in their crystallographic structure [6]. Physical properties that may be influenced by the nanodimensions are: transition temperatures [7], magnetic and electric properties [8], phase transition (the melting temperature can be decreased also by more than 100 ◦ C passing from bulk-to nano-materials) [9] and dissolution. Such effects can be predicted from thermodynamics (Laplace equation) and particles with dimensions below 15 nm behave quite differ- Nanosized particles 201 Nanoparticle diameter (nm) Atoms localized at the surface (%) 5 15 30 50 0 40 90 100 Fig. 8.2: The number of atoms on the surface (%) changes with the nanoparticle diameter (nm). ently from those that have a dimension over 30 nm. Several particular properties de-pend on the change of surface tension, ı , and on the derivative d ı / d r that is used in thermodynamic models [10]. 8.3 Nanoparticles and biosystems Several well-documented important changes occur when downscaling the dimension of particles. A quite well-known case is the change in the catalytic properties of gold.
eBook - PDF- Saeed Farrokhpay(Author)
- 2023(Publication Date)
- Arcler Press(Publisher)
CHEMISTRY OF NANOMATERIALS 6 CONTENTS 6.1. Introduction .................................................................................... 142 6.2. Fundamentals of Nanomaterials...................................................... 145 6.3. Characteristics of Nanoparticles (NPS) ............................................ 148 6.4. Classification of Nanomaterials....................................................... 155 6.5. Properties of Nanomaterials ............................................................ 157 6.6. Nanomaterial Processing and Synthesis .......................................... 163 6.7. Accumulation and Uniformity of Nanoparticles (NPS) .................... 176 6.8. Characterization of Nanoparticles (NPS) ......................................... 178 6.9. Application of Nanomaterials ......................................................... 180 References ............................................................................................. 186 CHAPTER The Fundamentals of Materials Chemistry 142 6.1. INTRODUCTION ‘Nano’ is a prefix that is used to describe anything that is 1 billionth of a millionth of something else, such as 1 millionth of something else. In his presentation titled ‘There’s Plenty of Space at the Bottom,’ presented at the meeting of the American Physical Society in December 1959, Richard P Feynman, a physics Nobel winner, introduced the concept of nanotechnology. Feynman was the first person to receive the Nobel Prize in Physics (Viswanathan et al., 2009; Sajanlal et al., 2011). Numerous breakthrough advances have been achieved in the fields of biology, chemistry, and physics since that time. By demonstrating Feynman’s principles of influencing matter on an atomic scale, these advancements have shown to be successful.
- Sabu Thomas, Gennady Zaikov, Valsaraj, Meera(Authors)
- 2010(Publication Date)
- CRC Press(Publisher)
It also refers to the fundamental understanding and resulting technological advances arising from the exploitation of new physical, chemical, and biological properties of systems that are intermediate in size, between isolated atoms and molecules and bulk materials, where the transitional properties between the two limits can be controlled. It cannot really be called chemistry, physics, or biology; researchers from all domains are studying very small things in order to better understand our world. 2 Sunny and Thomas The word “nano” is derived from the Greek word “nanos,” which means dwarfs. Richard Feynman (1918–1988), the Nobel laureate physicist, first mentioned the concept of “nanosized materials” (not yet using that name) in his speech (APS meeting Dec 29, 1959) titled There’s Plenty of Room at the Bottom [1]. Later in 1974, Professor Norio Taniguchi from Tokyo Science University, Japan, coined the term nanotechnology to describe the arts and science of manipulating atoms and molecules to create new systems, materials, and devices. The term nanotechnology was then reintroduced and popularized by California scientist and author Eric Drexler. In 1981, the advent of the scanning tunneling microscope enabled atom clusters to be seen, while in 1991 IBM demonstrated the ability to arrange individual xenon atoms using an atomic force instrument [2, 3]. 1.1.2. Nanomaterials “Nanomaterials” are the materials (crystalline or amorphous) that have one or more di-mensions in the range of 1 to 100 nm. The prefix “nano” means one billionth. In general, these particles (nanopowders, nanofibers, tubes, and thin films) could exist in powder form, dispersed in some medium, or as solid films [4]. Figure 1.1 shows the size of the nanoscale relative to some things we are more familiar with. We can see that the difference between a nanometer and a person is roughly the same as the difference between a person and celestial orbits.
eBook - ePub- (Author)
- 2018(Publication Date)
- Academic Press(Publisher)
10.3.14 Tensile Strength Determination 392- 10.4 Conclusion 392
- Acknowledgment 395
- Abbreviations 395
- References 396
- Further Reading 400
10.1 Nanoparticles in Pharmaceuticals
The implication of nanotechnology, which deals with Nanoparticles ranging in size from 1 to 1000 nm, in pharmaceuticals and more specifically drug delivery is set to continue to spread rapidly and gain worldwide attention. The most important use of Nanoparticles in pharmaceutical sciences is to reduce toxicity and side effects of drugs, however, carrier systems themselves may impose risks to the patient, such as toxicity. Moreover, development of Nanoparticles is one of the demanding areas of nanotechnology research and has been continually investigated for pharmaceutical application in the diagnosis, prevention, mitigation, and treatment of various diseases (Hughes, 2017 ). Nanoparticles in pharmaceutical sciences have been utilized with the purposes of decreasing toxicity and minimizing adverse effects of drug molecules by targeting to the specific site of action, reducing their dose through amended pharmacokinetics, decreasing dosing regularity by controlling drug release, and enhancing shelf life by improving stability. This eventually subsidizes to augmented safety, efficacy, patient compliance, and prolonged shelf life of the drug, and potentially abridged healthcare costs (Onoue et al., 2014 ; Maheshwari et al., 2018b ).Considering the fact that most nanoformulations developed or under development in research laboratories are meant for intravenous injection, the understanding of their characteristics is very important. In this regard, it is important to highlight that parenteral formulations must be aseptically prepared and may need to be filtered and terminally sterilized to minimize the presence of particulate matter and to avoid side effects due to bacterial endotoxins (Moondra et al., 2018
eBook - PDFNanoparticles
From Theory to Application
- Günter Schmid(Author)
- 2006(Publication Date)
- Wiley-VCH(Publisher)
Nobel Laureate Richard Feynman in his visionary lecture ‘‘There is plenty of room at the bottom’’ [1] inspired the concepts for the rapidly exploding research topic of nanotechnology. Although the term ‘‘nanotechnology’’ had not appeared on the horizon, Feynman said: ‘‘What I want to talk about is the problem of manipulating and controlling things on a small scale . . . What I have demonstrated is that there is room – that you can decrease the size of things in a practical way . . . I will not discuss how we are going to do it, but only what is possible in principle . . . We are not doing it simply because we haven’t yet gotten around to it.’’ Four decades later scientists have learnt that the manipulation of atoms, molecules and clusters on surfaces is feasible, and that new fundamental physics governs the properties of nano-objects. The miniaturization of structures by conventional [2] and electron-beam litho- graphy [3] is reaching the theoretical limits of ca. 50 nm. For the further minia- turization of chemical objects, alternative approaches must be developed. Fol- lowing Feynman’s vision, one may employ atoms and molecules as building units for the ‘‘bottom-up’’ assembly and construction of architectures with nanometer dimensions. Nanoparticles consisting of metals [4] (e.g., Au, Ag, Pt, and Cu) or semiconductors [5–9] (e.g., PbS, Ag 2 S, CdS, CdSe, and TiO 2 ) seem to be attractive units for the engineering of such structures. The unique electrical charging prop- erties of these particles [10], as well as their optical and photophysical features [11], such as size-controlled plasmon absorbance, photonic electron-hole pair genera- tion, and fluorescence, allow the addressing of particles by external electronic and photonic signals. A variety of synthetic methodologies for the preparation of Nanoparticles within a narrow size distribution are available [4].
eBook - ePubThe Sol-Gel Handbook
Synthesis, Characterization, and Applications
- David Levy, Marcos Zayat, David Levy, Marcos Zayat(Authors)
- 2015(Publication Date)
- Wiley-VCH(Publisher)
7 Nanoparticles and Composites Guido Kickelbick7.1 Introduction
Nanoparticles were identified in the last decade as an important class of materials for various emerging applications in optics, electronics, or the biomedical area. Many of the potential applications are based on two major changes when the scale of material structures is decreased: (i) the high surface-to-volume ratio and (ii) the change of electronic properties. It was realized at the outset of the nanotechnology hype that sol–gel-based materials will play an important role because of their straightforward preparation procedure combined with mild reaction conditions. This is advantageous because of the compatibility with processing steps in important technologies, such as electronic industry or the biomedical field. In addition, the wet chemical route applying molecular precursors allows an excellent control of size, composition, and morphology of the obtained materials. While the sol–gel process by definition is based on the formation of a sol (dispersion of colloidal particles in a liquid) in a first step, followed by further reaction into a gel (a porous inorganic network enclosing a continuous liquid phase), the production of Nanoparticles is strictly closer to a sol precipitation process than to the classical sol–gel chemistry. Nevertheless, all techniques are based on the chemical transformation of molecular precursors into extended inorganic networks, independent of whether this network is a macroscopic gel or just a small particle, and therefore they are generally summarized as sol–gel processes in a broader sense.In this chapter, the particles are divided into two subgroups: silica and metal oxide particles, because both systems have different challenges. In addition, the chapter is also divided in accordance with the preparation routes toward the Nanoparticles, namely, aqueous and nonaqueous sol–gel processes. For the implementation of the Nanoparticles into devices, it is often necessary to carry out a surface functionalization, which is also part of this chapter. In the concluding paragraphs, the effect of the thus formed particles on properties of nanocomposites has been discussed.
eBook - ePub- Ali Seyfoddin, Seyedehsara Masoomi Dezfooli, Carol Ann Greene(Authors)
- 2019(Publication Date)
- Woodhead Publishing(Publisher)
[6] .In this scenario, this chapter aims to cover the main aspects regarding lipid-based and polymer-based nanocarriers. Information related to their development and applications as therapeutic carriers for controlled drug release will be highlighted.4.2 Micro versus Nanoparticles: physicochemical properties for drug delivery
One of the most evident aspects when comparing microparticles and NPs is their different surface area and volume ratio [7 ,8] . For instance, it has been reported that there is a major probability of loose payload during preparation in the case of larger particles in comparison to smaller ones. In addition, drug efflux may be faster from smaller particles than from larger ones. Thus size affects almost every characteristic of particle function including its degradation, mechanical properties, clearance, uptake mechanisms, etc. [9 ,10] .In particular, for intravenously injected systems it is widely accepted that the size of particles is a key physical parameter that can be tuned to dramatically alter their biological function [11 ,12] . The size is an important factor in the design of DDS to increase the half-life in vivo and bioavailability after administration because it has a remarkable effect on particle distribution throughout the body [13 ,14] .Microparticles usually possess sizes from 1 to 5 µm, and because of its size they are typically removed by the reticuloendothelial system (RES), whereas larger microparticles are usually trapped in the capillary beds. In addition, particles of at least 10 μm and more were shown to produce embolization in the liver and lungs [15] . Always depending on the route of administration, particles with 500–1000 nm can be phagocytosed by macrophages and smaller particles can be endocytosed by phagocytic or nonphagocytic cells [9] . It has been well established that NPs greater than 200 nm are likely to be mechanically filtered in the spleen and ultimately removed by the cells of the phagocytic system; thus generally results in short circulation times in the bloodstream. Particles in the range size from 100 to 200 nm show longer circulation times as they are large enough to avoid liver uptake, but small enough to prevent leakage in the spleen [16 ,17] . It is important to consider that particles smaller than 100 nm leave the blood vessels through fenestrations in the endothelial lining [9 ,18] . NPs between 10 and 50 nm are small enough to penetrate the very small capillaries within the body tissues, being able to offer a more efficient distribution in certain tissues. However, these particles can be sequestered by the liver. Finally, NPs smaller than 5–6 nm are eliminated fast for extravasation and renal clearance and are consequently not interesting in therapy due to their low residence time in blood circulation [16 ,17]
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