Materials for Biomedical Engineering

Inorganic Micro- and Nanostructures

Valentina Grumezescu, Alexandru Grumezescu

• Publisher: Elsevier
• Year: 2019
• Print ISBN: 9780081028148
• eBook ISBN: 9780081028155
• Topic: Technology & Engineering
• Subtopic: Biotechnology in Medicine
• Index: Technology & Engineering

Materials for Biomedical Engineering: Inorganic Micro- and Nanostructures presents recent, specific insights in new progress, along with new perspectives for inorganic micro- and nano-particles. The main focus of this book is on biomedical applications of these materials and how their biological properties are linked to various synthesis methods and their source of raw materials. Recent information regarding optimized synthesis methods to obtain improved nano- and microparticles for biomedical use, as well as the most important biomedical applications of these materials, such as the diagnosis and therapy of cancer, are highlighted in detail.- Provides a valuable resource of recent scientific progress, highlighting the most well-known applications of inorganic micro- and nanostructures in bioengineering- Presents novel opportunities and ideas for developing or improving technologies in composites by companies, biomedical industries, and others- Features at least 50% of its references from the last 2-3 years

Chapter 1

Biomedical inorganic nanoparticles: preparation, properties, and perspectives

Magdalena Stevanović¹, Miodrag J. Lukić¹, Ana Stanković¹, Nenad Filipović¹, Maja Kuzmanović¹ and Željko Janićijević², ¹Institute of Technical Sciences of the Serbian Academy of Sciences and Arts, Belgrade, Serbia, ²School of Electrical Engineering, University of Belgrade, Belgrade, Serbia

Abstract

Nanotechnology has great potential in the biomedical field. Among other nanomaterials, inorganic nanoparticles have become extremely important since they possess unique physicochemical properties influenced by their specific surface structure. Consequently, inorganic nanoparticles exhibit enhanced functionalities such as biological response, antibacterial and antiviral properties, as well as optical, magnetic, and electrical responses. They have found applications in medicine, pharmacy, controlled drug delivery, optics, electronics, etc. In this chapter, reports on obtaining different metallic and ceramic inorganic nanoparticles such as gold, silver, selenium, copper, iron, zinc oxide, and hydroxyapatite for biomedical applications will be addressed. For each of these nanosystems, the main challenges regarding the currently achieved functional properties and further perspectives will also be presented.

Keywords

Gold; silver; selenium; copper; iron; zinc oxide; hydroxyapatite; nanoparticles

1.1 Introduction

Nanotechnology enables a better understanding of the fundamental biology, physics, chemistry, and technology of nanometer-scale objects (Mitragotri et al., 2015; Stevanović et al., 2008, 2013; Stevanović and Uskoković, 2009). It deals with the design, production, and operation of particle structures in the size range of approximately 1–100 nm. It has a wide range of applications in different areas of human activity such as in medicine, pharmacy, controlled drug delivery, optics, electronics, etc. For example, in medicine and pharmacy, a large number of studies have been focused on the use of nanoparticles as drug-delivery vehicles for therapeutics, since nanoparticles can interact with biological entities at the molecular level, and enable controlled and targeted delivery and passage through biological barriers. Moreover, in recent years, many different studies have revealed that some nanomaterials are intrinsically therapeutic. Such intense research has led to a more comprehensive understanding of cancer at the genetic, molecular, and cellular levels, providing an avenue for methods of increasing antitumor efficacy of drugs while reducing systemic side effects. It has been shown not only that nanoparticles can passively interact with cells, but also that they can actively mediate molecular processes to regulate cell functions (Kim and Hyeon, 2014). This is the case, for example, with the treatment of cancer via antiangiogenic mechanisms or the treatment of neurodegenerative diseases by effectively controlling oxidative stress (Kim and Hyeon, 2014). Among other nanomaterials, inorganic nanoparticles (Fig. 1.1) have attracted special attention since they possess unique properties such as size- and shape-reliant optical, magnetic, mechanical, and electrical properties, as well as biological responses, that is, antibacterial and antiviral properties (Stevanović et al., 2015). A wide variety of techniques for the synthesis of inorganic nanoparticles (metallic and ceramic) have been reported in the literature. Inorganic nanoparticles are made by the crystallization of inorganic salts, forming a three-dimensional arrangement of linked atoms where binding is mainly covalent or metallic. Recently, numerous inorganic nanoparticles have been successfully produced by various different synthetic techniques.

Figure 1.1 Types of inorganic nanoparticles which are used in the biomedical field.

However, the obtaining of highly uniform, biocompatible inorganic nanoparticles with adequate functional properties is still a challenge.

In this chapter, synthesis of different metallic and ceramic inorganic nanoparticles such as gold, silver, selenium, copper, iron, zinc oxide, and hydroxyapatite for biomedical applications will be addressed. For these nanosystems, the main challenges regarding the currently achieved functional properties and further perspectives will also be presented.

1.2 Gold Nanoparticles

Gold nanoparticles have occupied the attention of scientists for ages and are now heavily exploited in chemistry, biology, engineering, pharmacy, medicine, etc. (Giljohann et al., 2010; Hayat, 1989). These particles can be synthesized reproducibly, modified with apparently limitless chemical functional groups, and, in certain cases, characterized with atomic-level precision. Many examples of highly sensitive assays based upon gold nanoconjugates have been reported in the literature. Lately, among the numerous nanomaterials explored in therapeutic applications, those often found in clinical trials are gold nanoparticles (Mitragotri et al., 2015). Structures which behave as imaging-contrast agents, gene-regulating agents, drug carriers, and therapeutics have been designed and studied in the context of the diagnosis and therapy of many different diseases (Giljohann et al., 2010; Hayat, 1989). These materials have been chosen because of their unique physicochemical properties, which confer substantive advantages in cellular and medical applications. Fig. 1.2. shows different biomedical applications of gold nanoparticles.

Figure 1.2 Biomedical applications of gold nanoparticles. Source: Mind the graph.com

Gold nanoparticles can appear in different colors such as red, blue, or other colors, depending on their morphology, degree of agglomeration, and local environment. These visible colors reflect the underlying coherent oscillations of conduction-band electrons, plasmons, upon irradiation with light of appropriate wavelengths. These plasmons underlie the intense absorption and elastic scattering of light, which in turn forms the basis for many biological sensing and imaging applications of gold nanoparticles (Murphy et al., 2008; Qian et al., 2008; Kelly et al., 2002; Kreibig and Vollmer, 1995; Link and El-Sayed, 2003; Murphy et al., 2005; Link et al., 1999; Sharma et al., 2009; Rao et al., 2000; Daniel and Astruc, 2004; Turkevich et al., 1951; El-Sayed et al., 2005; Kim et al., 2006; Chen et al., 2005).

Recently, Piella et al. described a strategy for the synthesis of highly monodisperse, biocompatible, and functionalized sub-10-nm citrate-stabilized gold nanoparticles by a kinetically controlled seeded-growth strategy (Piella et al., 2016). They found that use of traces of tannic acid, together with an excess of sodium citrate, during nucleation is essential in the formation of a high number (7×10¹³ NPs/mL) of small ~3.5 nm gold seeds with a narrow size distribution. The reaction parameters such as pH, temperature, sodium citrate concentration, and gold precursor to seed ratio have been adjusted in order to produce gold nanoparticles with a precise control over their sizes between 3.5 and 10 nm.

Thiolate-protected gold nanoparticles, which are uniform in size, were synthesized with no requirement for purification by Azubel and Kornberg (2016). It has been shown that the thiol-to-gold ratio controlled the size of the particles, and the choice of thiol controlled the reactivity of the particles toward thiol exchange.

Lawrence et al. (2016) described a simple method for producing highly stable oligomeric clusters of gold nanoparticles via the reduction of chloroauric acid with sodium thiocyanate. The oligoclusters have a narrow size distribution and can be produced with a wide range of sizes and surface coats. By reducing dilute aqueous chloroauric acid with sodium thiocyanate under alkaline conditions, gold nanoparticles of about 2–3 nm, have been synthesized. The oligomeric clusters of these nanoparticles with narrow size distribution have been synthesized under ambient conditions via two methods. By varying the time between the addition of chloroauric acid to the alkaline solution and the subsequent addition of reducing agent (thiocyanate), in the delay-time method, the number of subunits in the oligoclusters have been controlled. The oligoclusters have been produced with sizes from ~3 to ~25 nm. It has been shown that this size range can be further extended by an add-on method utilizing hydroxylated gold chloride to autocatalytically increase the number of subunits in the as-synthesized oligocluster nanoparticles, providing a total range of 3–70 nm.

Green synthesis of gold nanoparticles using an aqueous extract of garcinia mangostana fruit peels have been described by Lee et al. (2016). The environmentally safe synthesis of gold nanoparticles has been performed by the reduction of aqueous gold metal ions in contact with the aqueous peel extract of the plant, Garcinia mangostana. The synthesized particles were mostly spherical in shape and with sizes of about 30 nm. From the FTIR results of this research, it has been concluded that phenols, flavonoids, benzophenones, and anthocyanins all may act as the reducing agent in the synthesis of gold nanoparticles. Phenols, ketones, and carboxyls were present in the leaves of Tamarindus indica L. leaves and these leaves have been used in the research of Correa et al. Correa et al. (2016) performed biosynthesis and characterization of gold nanoparticles using extracts of T. indica L. leaves. Phenols, ketones, and carboxyls for the synthesis of gold nanoparticles were identified by gas chromatography coupled to mass spectrometry and high-pressure liquid chromatography. The synthesis was performed at room temperature during 1 hour of reaction time. The results indicated the formation of gold nanoparticles with an average size of 52±5 nm.

Physical-vapor evaporation of metals on low vapor pressure liquids is a simple technique to synthesize nanoparticles and thin films, though only a little work has been conducted so far. Fujita et al. (2016) described obtaining gold...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• List of Contributors
• Series Preface
• Preface
• Chapter 1. Biomedical inorganic nanoparticles: preparation, properties, and perspectives
• Chapter 2. Inorganic composites in biomedical engineering
• Chapter 3. Structural interpretation, microstructure characterization, mechanical properties, and cytocompatibility study of pure and doped carbonated nanocrystalline hydroxyapatites synthesized by mechanical alloying
• Chapter 4. Multiparticle composites based on nanostructurized arsenic sulfides As4S4 in biomedical engineering
• Chapter 5. Quaternary ammonium compound derivatives for biomedical applications
• Chapter 6. Block copolymer micelles as nanoreactors for the synthesis of gold nanoparticles
• Chapter 7. Nanoparticles: synthesis and applications
• Chapter 8. Multimodal magnetic nanoparticles for biomedical applications: importance of characterization on biomimetic in vitro models
• Chapter 9. Aluminosilicate-based composites functionalized with cationic materials: possibilities for drug-delivery applications
• Chapter 10. Bioactive glass nanofibers for tissue engineering
• Chapter 11. Application of (mixed) metal oxides-based nanocomposites for biosensors
• Chapter 12. Metal nanoparticles and their composites: a promising multifunctional nanomaterial for biomedical and related applications
• Chapter 13. Hybrid metal complex nanocomposites for targeted cancer diagnosis and therapeutics
• Chapter 14. Nanocoatings and thin films
• Index