1 Nanomedicines: Applications and Toxicological Concerns
Mrunali Patel1, Rashmin Patel1, and Mahendra Rai2,3
1 Department of Pharmacy, Ramanbhai Patel College of Pharmacy, Charotar University of Science and Technology, (CHARUSAT), CHARUSAT Campus, Changa, GJ, India
2 Department of Biotechnology, Sant Gadge Baba Amravati University, Amravati, MH, India
3 Department of Microbiology, Nicolaus Copernicus University, Lwowska, Torun, Poland
1.1 Introduction
Nanotechnology is an evolving technology that has been researched for numerous uses, from material science to life science. A widely used description by National Nanotechnology Initiative, USA, defines nanotechnology as the designing, synthesis, and characterization of materials and structures smaller than 100 nanometers (nm in size or output limit), by controlling the shapes and sizes at the nanoscale (Parappurath et al. 2018; Bayda et al. 2020). The size of 100 nm, however, is not a rigid boundary; it varies depending on the application (McDonald et al. 2015). Recently, the design and manufacture of nanotechnology have risen, including nanoscience, nanomaterials, nanoparticles, nanomedicine, and nanotoxicology. The branch of science dedicated to the study of the peculiar properties of matter at the nanoscale is known as nanoscience (Bayda et al. 2020). The structures made up of aggregated or unbound nanoparticles apply to nanomaterials. As per the International Organization of Standardization, nanoparticles (NPs) are particles whose sizes in one, two, or three dimensions are within the range from 1 to 100 nm (Jeevanandam et al. 2018). Their measurements are equivalent to those of biomolecules such as proteins, DNA, hemoglobin, viruses, and cell membranes. Some of the significant and special characteristics of NPs are higher surface‐to‐mass ratios than the bulk material, altered quantum properties, and their ability to adsorb and hold other substances such as drugs, probes and proteins. They are both present in nature and can be produced by traditional industrial processes and techniques of nanomanufacturing (Shubhika 2013). The nanomaterials are classified based on diverse parameters such as dimensionality, morphology, composition, uniformity, agglomeration rate, and origin (Buzea and Pacheco 2017; Jeevanandam et al. 2018; Trotta and Mele 2019; Khan 2020) as tabulated in Table 1.1.
Nanotechnology employs novel, specific, and selective medicinal products at the nanoscale in the healthcare sector to develop nanomedicines. Nanomedicine is an emerging subdivision of nanotechnology that plays an important role in disease detection, surveillance, prevention, and remediation. The term nano means minuscule, extremely small; so, nanomedicine is concerned with drug formulations in the nano range of sizes (nanoformulations). The nanoformulations can be utilized for delivery of an impressive range of therapeutic drugs by encapsulation or attachment on the surface for a targeted, sustained, and controlled release to almost any tissue/organ/area of the body (Mukherjee et al. 2014; Krukemeyer et al. 2015; Ventola 2017; Fadeel and Alexiou 2020). Possible applications include: nanorobots, nanoscale medicines and targeted delivery of medicines, nanocarriers for drug delivery such as nanocrystal, polymeric NPs, magnetic NPs, mesoporous silica NPs, liposomes, micelles, dendrimers, quantum dots, iron oxide, carbon nanotubes, antimicrobial medical dressings, in vivo imaging techniques, bone and dental prostheses, tissue regeneration, etc. Nanotechnology also enables better identification and understanding of biomarkers. Further, benefits achieved are analysis of the disease stage, three‐dimensional (3D) nanomaterials for injury site, immobilized stem cells, blood glucose metering, delivery of insulin, guided implantation, etc. The financial implications of the use of nanotechnology in medicine were projected to rise to $528 billion by 2019 and will continue to grow dramatically in the coming years, according to recent industry forecasts. Further development in this field enables technology for patient‐specific, targeted, and regenerative medicine (Farjadian et al. 2019).
Table 1.1 An overview of the classification of nanomaterials based on various parameters with a few examples and applications.
Sources: Based on Buzea and Pacheco (2017), Jeevanandam et al. (2018), Trotta and Mele (2019) and Khan (2020).
| Parameter | Classes | Examples | Applications | |
|---|---|---|---|---|
| Dimensionality | Zero‐dimensional (0D) | Quantum dots Dendrimers Fullerenes | Cell marker, emulsifier in solution, reinforcement filler within a solid matrix | |
| One‐dimensional (1D) | Nanowires Nanotubes Nanofibers Nanorods | Electronics, magnetism, optics, and catalysis | ||
| Two‐dimensional (2D) | Thin films Nanocoatings Nanoplates | Optoelectronics, catalysts, sensors, solar cells, energy storage facilities | ||
| Three‐dimensional (3D) | Nanocomposites (nanofillers in bulk matrix composed of ceramics, metals, or polymers) Nanostructured materials (nanoporous structures as aerogels, block polymers, nanostructured metals and alloys) | Packaging materials, shape‐memory materials, coatings with nanoprotrusions, catalysts | ||
| Morphology | Low aspect ratio | Nanospheres, nanocubes, nanopyramids | Biomedical applications, plasmonic sensing platform (silver nanocube), optical applications | |
| High aspect ratio | Nanowires, nanotubes, nanobelts, nanofibres | Separation and isolation of specific analyte from complex mixtures, targeted delivery, magnetic resonance imaging | ||
| Chemical compositiona | Metal and metal alloys | Silver | Medical diagnostic, antibacterial, conductive, and optical applications | |
| Copper | Catalyst, lubricant additive, electrical and thermal conductor, antibacterial agent | |||
| Gold | Drug delivery, medical testing, cancer detection, electronics | |||
| Iron | Bactericide in water treatment, superparamagnetic in drug delivery, data recording, and magnetic detection | |||
| Aluminum–magnesium/titanium–aluminum alloys | Aerospace and high‐temperature applications | |||
| Metal oxides | Titanium dioxide | Filter for cosmetics, chemical catalyst for cleaning product and wall paint, antibacterial agents for filtration devices | ||
| Zinc oxide |
Catalytic,
|