Nanostructures for Antimicrobial Therapy

Anton Ficai, Alexandru Mihai Grumezescu

• Publisher: Elsevier
• Year: 2017
• Print ISBN: 9780323461528
• eBook ISBN: 9780323461511
• Topic: Physical Sciences
• Subtopic: Physical & Theoretical Chemistry

Nanostructures for Antimicrobial Therapy discusses the pros and cons of the use of nanostructured materials in the prevention and eradication of infections, highlighting the efficient microbicidal effect of nanoparticles against antibiotic-resistant pathogens and biofilms.Conventional antibiotics are becoming ineffective towards microorganisms due to their widespread and often inappropriate use. As a result, the development of antibiotic resistance in microorganisms is increasingly being reported. New approaches are needed to confront the rising issues related to infectious diseases. The merging of biomaterials, such as chitosan, carrageenan, gelatin, poly (lactic-co-glycolic acid) with nanotechnology provides a promising platform for antimicrobial therapy as it provides a controlled way to target cells and induce the desired response without the adverse effects common to many traditional treatments.Nanoparticles represent one of the most promising therapeutic treatments to the problem caused by infectious micro-organisms resistant to traditional therapies. This volume discusses this promise in detail, and also discusses what challenges the greater use of nanoparticles might pose to medical professionals. The unique physiochemical properties of nanoparticles, combined with their growth inhibitory capacity against microbes has led to the upsurge in the research on nanoparticles as antimicrobials. The importance of bactericidal nanobiomaterials study will likely increase as development of resistant strains of bacteria against most potent antibiotics continues.- Shows how nanoantibiotics can be used to more effectively treat disease- Discusses the advantages and issues of a variety of different nanoantibiotics, enabling medics to select which best meets their needs- Provides a cogent summary of recent developments in this field, allowing readers to quickly familiarize themselves with this topic area

Chapter 1

Antimicrobials

Meeting the Challenges of Antibiotic Resistance Through Nanotechnology

Bhaskar Das, and Sanjukta Patra Indian Institute of Technology Guwahati, Guwahati, India

Abstract

Antibiotics are one of the antimicrobials that have been widely exploited to control infectious diseases. The successful use of antibiotics is challenged by the rapid emergence of antibiotic resistance and the need for better methods of delivery. To overcome the problem of drug resistance, novel antimicrobial agents are needed to which the clinical isolates cannot easily develop resistance. Nanomaterials seem to be an answer to the problem because their antimicrobial effects are dependent on their ability to affect multiple biological pathways. To develop microbial resistance to antimicrobial nanoparticles (NPs), concurrent mutations have to occur making development of microbial resistance to NPs less likely. The utilization of nanocarriers for conventional antibiotics has been proven to enhance their antimicrobial activity against drug-resistant microbial strains showing potential to overcome the growing menace of drug resistance. This chapter highlights the current advances underlying emergence of antibiotic-resistant pathogens and endorses the use of nanomaterials to counteract antimicrobial resistance and the delivery of antimicrobial drugs.

Keywords

Antibiotic resistance; Antimicrobials; Better delivery; Nanoparticle-based delivery

Chapter Outline

1. Introduction

2. Current Status of the Menace of Antimicrobial Resistance

3. Antimicrobial Classes and Their Current Effectiveness With Respect to Emerging Drug Resistance

3.1 Classification on the Basis of Spectrum of Activity

3.2 Classification on the Basis of Nature of Effect

3.3 Classification on the Basis of Mode of Action

3.3.1 Cell Wall Synthesis Inhibitors

3.3.2 Cell Membrane Function Inhibitors

3.3.3 Protein Synthesis Inhibitors

3.3.4 Nucleic Acid Synthesis Inhibitors

3.3.5 Metabolic Process Inhibitors

4. Microbial Resistance Mechanism to Antimicrobials

4.1 Antibiotic Inactivation

4.1.1 Hydrolysis-Based Antibiotic Inactivation

4.1.2 Group Transfer-Based Enzymatic Inactivation

4.1.3 Redox Process-Based Antibiotic Inactivation

5. Application of Nanotechnology to Counter Antimicrobial Resistance

5.1 Nanomaterials as Antimicrobials

5.1.1 Silver Nanoparticles

5.1.2 Zinc Oxide Nanoparticles

5.1.3 Titanium Dioxide Nanoparticles

5.1.4 Gold Nanoparticles

5.1.5 Copper Nanoparticles

5.1.6 Chitosan

5.1.7 Nitric Oxide-Releasing Nanoparticles

5.1.8 Carbon Nanotubes

6. Role of Nanoparticles in Overcoming the Challenge of Antimicrobial Drug Delivery

6.1 Liposome-Mediated Antimicrobial Delivery

6.1.1 Polymeric Nanoparticles

6.1.2 Solid Lipid Nanoparticles

6.1.3 Dendrimers

7. Conclusions

Acknowledgment

References

Further Reading

1. Introduction

Antimicrobials are probably one of the most successful forms of chemotherapy in medical history and have contributed significantly to controlling infectious diseases that threaten the existence of human civilization (Aminov, 2010). The word antimicrobial is derived from the Greek words anti (against), mikros (little), and bios (life) and refers to agents that kill microorganisms or cause growth inhibition. Antibiotics are substances that are produced by microorganisms that inhibit or kill other microorganisms. On the contrary, an antimicrobial is a natural (plant or animal), semisynthetic, or synthetic substance that kills or inhibits microbial growth with no or minimal damage to the host. Antimicrobials act against all microbial varieties and thus are classified according to the microbial group they act against. Antibacterials act against bacteria, antivirals act against viruses, antifungals act against fungi, and antiprotozoals act against protozoa (www.amrls.cvm.msu.edu). Antimicrobials that kill microbes are known as microbicidal, while those that inhibit microbial growth are referred to as biostatic. Use of antibiotics is not only restricted to the modern “antibiotic era” but dates back to ancient civilizations. Traces of tetracycline have been determined in human skeletal remains from the ancient Sudanese Nubia dating back to 350–550 CE, and Roman period skeletons from Egypt indicated exposure to tetracycline-containing material in their diet (Nelson et al., 2010; Basset et al., 1980). In India, Ayurveda, the oldest healthcare system in the world (about 5000 years old), has references to various types of microorganisms that cause diseases and stresses the need to destroy them to preserve human health. Many Ayurvedic drugs were known to be effective against common microbial infections such as Mycobacterium tuberculosis (treated by Suvarna Bhasma or gold calyx), malaria (treated using Mahasudarshan Kwath), and surgical prophylaxis (treated using Triphala Guggulu) (Sharma et al., 2014). With the advent of the germ theory of disease, the vital role of microbes in causing infectious diseases has been established, setting the stage for the beginning of the “modern antibiotic era.” The major breakthrough in field of antibiotics came in 1928 when Alexander Fleming discovered the antibiotic penicillin from Penicillium rubens. Penicillin has found clinical applications to successfully treat many fatal infectious diseases such as Streptococcus infection, gonorrhea, strep throat, and pneumonia. In 1935, Gerhard Domagk developed the first synthetic antibacterial sulfonamide with tremendous clinical success in treating diseases such as meningitis, child bed fever, and pneumonia. The discovery and clinical application of such antibiotics set the paradigm for the search for new antimicrobials by other researchers. The clinical value of an antimicrobial would be compromised by development of microbial resistance against it. Even before the clinical use of antibiotics, Alexander Fleming's research group discovered a bacterial penicillinase that can inactivate penicillin. Uncontrolled widespread use of penicillin resulted in the emergence of penicillin-resistant strains, mostly Staphylococci, and most countries restricted penicillin use “by prescription” only. To counteract this, a semisynthetic penicillin variety, methicillin, which is insensitive to penicillinase, was developed and used successfully for antibacterial chemotherapy. However, after few years of clinical use, methicillin-resistant strains of Staphylococcus aureus (MRSA) emerged, which has become a current challenge faced by antimicrobial therapy worldwide. The pattern of emergence of antibiotic resistance is the same for other antibiotics that were commercially available in the latter half of the 20th century (www.amrls.cvm.msu.edu). Mortality rates caused by multidrug-resistant bacterial infection have been reported to be quite high in the European Union and the Unites States, being 25,000 and 63,000 patients per year, respectively. Scientists have warned that the world will return to a preantibiotic era plagued by life-threatening microbial infections on the basis of a recent antibiotic resistance gene database that lists the existence of more than 20,000 antibiotic-resistant genes of 400 types predicted from available genome sequences (Liu and Pop, 2009). Thus discovery of novel antimicrobial agents to which microbes cannot develop resistance easily is one of the major medical concerns of the 21st century. The development of new antimicrobials alone will not be effective for antimicrobial therapy unless efficient drug delivery strategies are developed. Inefficient drug delivery would result in decreased therapeutic index of the antimicrobials along with local and systemic side effects. The current clinical application of nanotechnology has the potential to revolutionize antimicrobial therapy by overcoming the problems associated with conventional therapy. Nanoparticles (NPs) could serve as novel antimicrobial agents with less chances of development of microbial resistance (Huh and Kwon, 2011). Also the therapeutic index of antimicrobials can be improved by loading drugs on NP-based carriers, in contrast to its free drug counterparts. Use of NPs for antimicrobial delivery will significantly increase the drugs' serum solubility, prolong the lifetime of systemic circulation of the drug, sustain drug release in target tissues, and make use of combination therapy by delivering multiple drugs to the same target cell (Zhang et al., 2010)....

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• List of Contributors
• Series Foreword
• Series Preface
• Preface
• Chapter 1. Antimicrobials: Meeting the Challenges of Antibiotic Resistance Through Nanotechnology
• Chapter 2. Nanoantimicrobials: Activity, Benefits, and Weaknesses
• Chapter 3. Sensitive and Selective Assay of Antimicrobials on Nanostructured Materials by Electrochemical Techniques
• Chapter 4. Antimicrobial Polymeric Nanostructures
• Chapter 5. Thin Degradable Coatings for Optimization of Osseointegration Associated With Simultaneous Infection Prophylaxis
• Chapter 6. Antimicrobial Nanostructures for Neurodegenerative Infections: Present and Future Perspectives
• Chapter 7. Nanocarriers and Their Potential Application as Antimicrobial Drug Delivery
• Chapter 8. Delivery of Antimicrobials by Chitosan-Composed Therapeutic Nanostructures
• Chapter 9. Antimicrobial Thin Coatings Prepared by Laser Processing
• Chapter 10. Antimicrobial Photodynamic Therapy With Nanoparticles Versus Conventional Photosensitizer in Oral Diseases
• Chapter 11. Applications of 19F Magnetic Resonance Spectroscopy and Imaging for the Study of Nanostructures Used in Antimicrobial Therapy
• Chapter 12. Essential Oils and Nanoparticles: New Strategy to Prevent Microbial Biofilms
• Chapter 13. Nanocarrier-Assisted Antimicrobial Therapy Against Intracellular Pathogens
• Chapter 14. Preparation and Antimicrobial Activity of Inorganic Nanoparticles: Promising Solutions to Fight Antibiotic Resistance
• Chapter 15. Outer Membrane Vesicles of Gram-Negative Bacteria: Nanoware for Combat Against Microbes and Macrobes
• Chapter 16. Organic Nanocarriers for the Delivery of Antiinfective Agents
• Chapter 17. Nanocarriers for Plant-Derived Natural Compounds
• Chapter 18. Fullerene Derivatives in Photodynamic Inactivation of Microorganisms
• Chapter 19. Silver Iodide Nanoparticles as an Antibiofilm Agent—A Case Study on Gram-Negative Biofilm-Forming Bacteria
• Chapter 20. Nanoformulations for the Therapy of Pulmonary Infections
• Chapter 21. Nanocarriers for Photosensitizers for Use in Antimicrobial Photodynamic Therapy
• Chapter 22. Zinc Oxide Nanostrucures: New Trends in Antimicrobial Therapy
• Chapter 23. Copper-Based Nanoparticles as Antimicrobials
• Chapter 24. Antimicrobial Applications of Superparamagnetic Iron Oxide Nanoparticles: Perspectives and Challenges
• Chapter 25. Silica Nanoparticles as a Basis for Efficacy of Antimicrobial Drugs
• Chapter 26. Silver Nanoparticles as Antimicrobial Agents: Past, Present, and Future
• Chapter 27. Encapsulation of Lethal, Functional, and Therapeutic Medicinal Nanoparticles and Quantum Dots for the Improved Diagnosis and Treatment of Infection
• Chapter 28. Advanced Nanocomposites With Noble Metal Antimicrobial Nanoparticles: How to Design a Balance Among Antimicrobial Activity, Bioactivity, and Safe Delivery to the Place of Infection
• Chapter 29. Clinical Developments in Antimicrobial Nanomedicine: Toward Novel Solutions
• Chapter 30. Recent Citation Classics in Antimicrobial Nanobiomaterials
• Index