Nanotechnology in Medicine:
The Medicine of Tomorrow and Nanomedicine
Logothetidis S
Aristotle University of Thessaloniki, Physics Department
Lab for Thin Films - Nanosystems & Nanometrology, GR-54124 Thessaloniki, Greece
Lab for Thin Films - Nanosystems & Nanometrology, GR-54124 Thessaloniki, Greece
Abstract
Nanotechnology is an emerging technology with enormous potential in information and communication technology, biology and biotechnology, medicine and medical technology. Novel nano- and bio-materials, and nanodevices are fabricated and controlled by nanotechnology tools and techniques, which investigate and tune the properties, responses and functions of living and non-living matter, at sizes below 100 nm. The current advances of nanotechnology in modern medicine are presented and discussed. The potential medical applications are predominantly in detection, diagnostics (disease diagnosis and imaging), monitoring, and therapeutics. The availability of more durable and better prosthetics, and new drug-delivery systems are of great scientific interest and give hope for cancer treatment and minimum invasive treatments for heart disease, diabetes and other diseases. Many novel nanoparticles and nanodevices are expected to be used, with an enormous positive impact on human health. The vision is to improve health by enhancing the efficacy and safety of nanosystems and nanodevices. Products based on nanotechnology in medicine and medical technology are reaching the market, with an anticipated enormous positive impact on human health, in the coming years. The development of specific guidance documents at a European level for the safety evaluation of nanotechnology products in medicine is strongly recommended and the need for further research in nanotoxicology, is identified. Ethical and moral concerns also need to be addressed in parallel with the new development.
1.
Introduction
Nanoscale is generally considered to be at a
size below 0.1 µm or 100 nm (a nanometer is one billionth of a metre, 10-9 m)
(Figure 1). Nanoscale science (or nanoscience) studies the phenomena, properties
and responses of materials at atomic, molecular and macromolecular scales, and
in general at sizes between 1-100 nm. In this scale, and especially below 5 nm,
the properties of matter differ significantly (i.e. quantum scale effects play
an important role) from that at a larger particulate scale. Nanotechnology is
then the design, the manipulation, the building, the production and
application, by controlling the shape and size, the propertiesresponses and
functionality of structures, devices and systems of the order or less than 100
nm. Figure 1 shows objects and living units whose size is or occur basically in
the nanoscale, are also shown higher order structures of biological units or
organisms at micro- meso- and macroscale, made by nature the last 4 billion
years due to the ability to self- assemble and selforganize. In the same figure
(on the right) are shown those objects man made at nano- and microscale during
the last few years. Nowadays, scientists and technologists are learning from
nature, and by applying the laws of physics, the properties of chemistry and
the principles of biology, they create the era of nanotechnology.
Nanotechnology is considered an emerging technology due to the possibility to
advance well established products and to create new products with totally new
characteristics and functions with enormous potential in a wide range of
applications. In addition to various industrial uses, great innovations are
foreseen in information and communication technology, biology and biotechnology,
medicine and medical technology, in metrology, etc. It is anticipated that
nanotechnology can have an enormous positive impact on human health. Relevant
processes of living organisms occur basically at nanometer scale, elementary
biological units like DNA, proteins or cell membranes are of this dimension
(Figure 1). By the means of nanotechnology, these biological units are going to
be better comprehended so that they can be specifically guided or directed.
Miniaturisation down to nanometer scale provides to become an essential feature
of biomedical products and procedures in postgenomic era. Nanoscale devices
could be 100 to 10,000 times smaller than human cells but are similar in size
to large biomolecules such as enzymes and receptors. Nanoscale devices smaller
than 50 nm can easily enter most cells, and those smaller than 20 nm can move
out of blood vessels as they circulate through the body.
Huge aspirations are coupled to nanotechnological developments in modern
medicine (Nanotechnology, Biotechnology, Information Technology & Cognitive
Science - NBIC developments). The potential medical applications are
predominantly in diagnostics (disease diagnosis and imaging), monitoring, the
availability of more durable and better prosthetics, and new drug-delivery
systems for potentially harmful drugs1 , as shown in Figure 2. For example,
nanoscaled diagnostics are expected to identify in the becoming, giving the
opportunity to intervene specifically prior to a symptomatically detected onset
disease. Biomedical nanotechnology presents revolutionary opportunities in the
fight against many diseases. An area with near-term potential is detecting
molecules associated with diseases such as cancer, diabetes mellitus,
neurodegenerative diseases, as well as detecting microorganisms and viruses
associated with infections, such as pathogenic bacteria, fungi, and HIV
viruses. For example, in the field of cancer therapy, promising novel
nanoparticles will respond to externally applied physical stimuli in ways that make
them suitable therapeutics or therapeutic delivery systems. Another important
field of application for nanotechnology are biomaterials used for example in
orthopedic implants or as scaffolds for tissue engineered products.
Nanotechnology might yield nano-structured surfaces preventing non-specific
protein adsorption. Control of surface properties at nanolevel was shown to
increase the biocompatibility of the materials.
2.
Nanomaterials and nanoparticles in
medicine: A new concept
Novel nanomaterials and nanoparticles are envisaged to have a major impact on a number of different relevant areas. Materials with high performance and unique properties can be produced, that traditional synthesis and manufacturing methods could not create.
Future nanoparticles should act as
drug-delivery and drug- targeting systems. Due to their smallness they are not
recognized by the human body, migrate through cell membranes beneath a critical
size and are able to pass the blood - brain barrier. These characteristics are
used to develop nanoscaled ferries, which transport high potential
pharmaceutics precisely to their destination. There are different kinds of
nanoparticles which are suitable to be applicable in drug- and gene- delivery,
probing DNA structures, etc, and are categorized as: liposomes, polymer
nanoparticles (nanospheres and nanocapsules), solid lipid nanoparticles,
nanocrystals, polymer therapeutics such as dendrimers, fullerenes (most common
as C60 or buckyball, similar in size of hormones and peptide a-helices),
inorganic nanoparticles (e.g. gold and magnetic nanoparticles). Carbon
nanotubes (diameter of 1-20 nm, as shown in Figure 3a) and inorganic nanowires
exhibit extraordinary mechanical, electric, electronic, thermal, and optical
properties offering the electronic industry properties that few materials
platforms could ever hope to match. Carbon nanotubes, and magnetic iron oxide
nanoparticles, gold-coated silica nanoshells, can transform electro-magnetic
energy into heat, causing a temperature increase lethal to cancer cells merely
by increasing the magnetic field or by irradiation with an external laser
source of near infra red light at the very location where these nanoparticles
are bound to or internalised within tumour cells2 . Quantum dots (nanometer sized
semiconductor nanocrystals with superior fluorescent properties, as shown in
Figure 3b) possess remarkable optical and electronic properties that can be
precisely tuned by changing their size and composition, due to their very small
size (2-10 nm). Due to their relatively inexpensive and simple synthesis,
quantum dots have already entered the market for experimental biomedical
imaging applications. Quantum dots can be made to emit light at any wavelength
in the visible and infrared ranges, and can be inserted almost anywhere,
including liquid solution, dyes etc. Quantum dots can be attached to a variety
of surface ligands, and inserted into a variety of organisms for in-vivo
research.
Dendrimers (complex almost spherical
macromolecules with diameter 1-10 nm, shown in Fig.3c) have improved physical,
chemical, and biological properties compared to traditional polymers. Some
unique properties are related to their globular shape and the presence of
internal cavities offering the possibility as medical nanovehicles. Dendrimers
have a tree-like structure with many branches where a variety of molecules,
including drugs can be attached. Less than 5 nm in diameter, dendrimers are
small enough to slip through tiny openings in cell membranes and to pass
vascular pores and tissues in a more efficient way than bigger polymer
particles. In experiments reported in Cancer Research, University of Michigan
scientists attached methotrexate, a powerful anticancer drug, to branches of
the dendrimer (Figure 3c). On other branches, they attached fluorescent imaging
agents and a vitamin called folic acid2,3. In addition to these examples of
individual nanoparticles, novel biomaterials can be constructed using
structural surface modifications of macro-, microas well as nanomaterials.
Control of surface properties at nanolevel was shown to increase the
biocompatibility of the materials2 . Nanoparticles, as shown in Figure 4, being
the fundamental elements of nanotechnology, can be applied in various ways such
as fluorescent biological markers, as markers for detection of proteins,
probing of DNA structures and for separation and purification of biological
molecules and cells, and they can also be used for magnetic resonance imaging
enhancement, tumour destruction via heating, tissue engineering and drug, gene
delivery. As an example, two kinds of nanoparticles that are suitable to be
applicable at least in drug-delivery will be described: First, gold
nanoparticles (3-20 nm), that are gold composites with dielectrical cores and
golden shells. By choosing the right ratio of core to shell diameters the
particle can be tuned to absorb highly in the near infrared, and by irradiation
with such wavelength can be heated, even in deeper skin areas. If the particles
are embedded in a temperature sensible hydrogenlmatrix, the matrix will
collapse and the included agents will be released at a critical temperature.
For
applications to medicine and physiology, these nanomaterials, nanoparticles and
devices can be designed to interact with cells and tissues at a molecular
(i.e., subcellular) level with a high degree of functional specificity, thus
allowing a degree of integration between technology and biological systems not
previously attainable. It should be appreciated that nanotechnology is not in itself
a single emerging scientific discipline but rather a meeting of traditional
sciences such as chemistry, physics, materials science, and biology to bring
together the required collective expertise needed to develop these novel
technologies4 . On the other hand, due to advances in biochemical research and
molecular biology diseases can put down to molecular abnormalities. Molecular
imaging should detect the corresponding molecular signatures of diseases and
use it for medical diagnosis. This should ideally lead to a diagnose and
therapy before occurrence of symptoms. In molecular imaging, an imaging
molecule is coupled to a transport molecule or particle, which possesses a
targeting unit (e.g. special receptors, ligands or peptides). The target finding
system should be a specific molecular marker of a certain disease thus the
contrast medium accumulates within the sick tissue. Molecular imaging is
developed for several diagnostic procedures such as magnetic resonance,
ultrasonic imaging, as well as nuclear and optical imaging technologies.
3.
Nanotechnology Tools in Medicine.
Different methods for the synthesis of
nanoengineered materials and devices can accommodate precursors from solid,
liquid or gas phases and encompass a tremendously varied set of experimental
techniques. A detailed presentation of these are beyond the scope of this
review. In general, however, most synthetic methods can be classified into two
main approaches: “top-down” and “bottom-up” approaches and combinations of
them. “Top-down” (photolithography, microcontact printing) techniques begin
with a macroscopic material or group of materials and incorporate smaller-scale
details into them, whereas “bottom-up” (organic-synthesis, self-assembly)
approaches, begin by designing and synthesizing custom-made molecules that have
the ability to self-assemble or self-organize into higher order mesoscale and
macroscale structures4 . There are several nanotechnology-based synthesis
techniques of these materials. For example, carbon nanotubes, are developed by
electric arc discharge, laser ablation, and chemical vapour deposition
techniques. Various inorganic nanotubes are developed by arc discharge, and
laser ablation, as well as through appropriate chemical reactions. Nanowire
properties can differ distinctly from those of their corresponding crystalline
bulk materials, though, some properties are similar. Nanowires can be
synthesized using a large variety of materials such as metals, e.g. Ag,
semimetals, e.g. Bi, semiconductors, e.g. CdS, and superconductors. The most
common synthesis methods are template-assisted synthesis, including vapour and
electrochemical deposition, and vapour-liquid-solid growth, especially
successful for semiconductor nanowires. Dendrimers were first synthesized by an
iterative synthetic methodology. The iterative sequence of reaction steps leads
to a higher generation dendrimer after each iteration. The creation of
dendrimers, using specifically-designed chemical reactions, is one the best
examples of controlled hierarchical synthesis, an approach that allows the
“bottom-up” creation of complex systems. The functional end groups can be
modified for various purposes, including sensing, catalysis or biochemical
activity. Other advanced applications of micro- and nanotechnology in medicine
are the microchip-based drug delivery systems, which are devices incorporating
micrometer-scale pumps, valves and flow channels. They allow controlled release
of single or multiple drugs on demand. Micro- and nanotechnology-based methods
(e.g., UV-photolithography, reactive ion etching, chemical vapour deposition,
electron beam evaporation) can be used for the fabrication of these
silicon-based chips. A myriad of studies is available for applications of
micro- and nanotechnologies in chips for medical molecular diagnostics. Key
words are for example DNA microarrays (gene chips), protein microarrays
(protein chips), lab-on-a-chip devices (Figure 5a), and cell chips. Basically,
these devices or systems are constructed using techniques inspired from micro/nanoscale
fabrication methods, that are used for processing, manipulation, delivery,
analysis or construction of biological and chemical entities. Inkjet printing
methods are used in DNA microarrays for human genomics and in protein
microarrays (or protein chips), which are useful for molecular diagnostics. For
the subsequent readout detection either fluorescence- or radionuclide-based
markers, or surface plasmon resonance spectroscopy can be applied.
In
order to study and explore these rich and complex systems, highly sophisticated
experimental, theoretical and modelling tools are required. Especially, the
visualization, characterization, and manipulation of materials and devices
require sophisticated imaging and quantitative techniques with spatial and
temporal resolutions on the order of 10-6 (a micron — a red cell is 7 microns)
and below to the molecular level. In addition, these techniques are critical
for understanding the relationship and interface between nanoscopic and
mesoscopic/macroscopic scales, a particularly important objective for
biological and medical applications. As such, further nanotechnological
advances will necessitate parallel progress of these physical characterization
techniques. Examples of important tools available at the moment include: highly
focused (i.e., 1–2 ìm) synchrotron X-ray sources and related techniques that
provide detailed molecular structural information by directly probing the
atomic arrangement of atoms (Figure 5b); scanning probe microscopy (STM, AFM) that
allow three dimensional-type topographical atomic and molecular views or
optical responses (SNOM) of nanoscale structures (Figure 5c); in situ
monitoring techniques that allow the monitoring and evaluation of building
block assembly and growth13; ellipsometry, an optical method, with the
capability of measuring in liquid environment (e.g, protein solution) to study
protein and cells adsorption on solid surfaces6 , it has been employed to
discriminate and identify bacteria at the species level, and is very promising
for analytical purposes in biochemistry and in medicine.
4.
Medical Applications of Nanotechnology and Nanomedicine
Nanotechnology offers important new tools
with a great impact on many areas in medical technology. It provides
extraordinary opportunities not only to improve materials and medical devices
but also to create new “smart” devices and technologies where existing and more
conventional technologies may be reaching their limits. In the following these
definitions related with new research areas and terms (i.e. nanobiotechnology,
nanomedicine, nanodevices, “nanorobots”) will be given and then some of myriad
applications of nanotechnology in modern medicine will be discussed in more
detail
Nanomedicine: The convergence of recent
advances in nanotechnology with modern biology and medicine has created the new
research domain of nanobiotechnology. The use of nanobiotechnology in medicine
is termed nanomedicine. Thus, nanomedicinean offshoot of Nanotechnology,
referring to highly specific medical intervention at the molecular scale for
therapeutic purposes (involving curing diseases or repairing damaged tissues),
and for the development of diagnostics for rapid monitoring, targeted cancer
therapies, localized drug delivery, improved cell material interactions,
scaffolds for tissue engineering, and gene delivery systems. Successful
research and development in nanomedicine where ultimately patients can benefit
from these new technologies require the interaction of a multitude of
disciplines including material science and engineering, cellular biology and
clinical translational research.
Many scientific as well as economic activities are expected to
accelerate medical research and development. Several medical devices2 have
already benefited from recent developments in micro- nanotechnology (see Table
1) and are in use or are currently being commercialized (Figures 5 and 7).
Nanomaterials and biological structures are approximately of the same size,
which allows for unique interactions between biological systems and synthetic
materials for analytical, diagnostic and therapeutic applications.
nisms in living cells. “Nanorobots” and
nanodevices: Such future devices are, for example, the artificial mechanical
red blood cell or “respirocyte” (spherical shape of 1ìm diameter) and an
artificial mechanical white blood cell of microscopic size, called a
“microbivore” (3.4 ìm major axis diameter and 2.0ìm minor axis diameter). The
“respirocyte” is expected to be able to deliver more oxygen to the tissues than
natural red blood cells and to manage carbonic acidity. Primary medical
applications of respirocytes would include transfusable blood substitution;
partial treatment for anemia, lung disorders, enhancement of
cardiovascular/neurovascular procedures, tumour therapies and diagnostics,
prevention of asphyxia, artificial breathing, and a variety of sports,
veterinary and battlefield. The primary function of “microbivore” is to destroy
microbiologic pathogenat the cellular level, performing in-vivo cytosurgery.
The most likely site of pathologic function in the cell is the nucleus – more
specifically, the chromosomes. In one simple cytosurgical procedure called
“chromosome replacement therapy”, a “nanorobot” controlled by a physician would
extract existing chromosomes from a particular diseased cell and insert new
ones in their place, in that same cell. If the patient chooses, inherited
defective genes could be replaced with non defective base-pair sequences,
permanently curing a genetic disease. Engineered bacterial “biobots” (synthetic
microbes) may be designed to produce useful vitamins, hormones, enzymes or
cytokines in which a patient’s body was deficient or to selectively absorb and
metabolize harmful substances such as poisons, toxins etc into harmless end
products.
Biocompatibility and Orthopedic implants: An important field of
application for nanotechnology in medicine is the biomaterials, used for
example in orthopedic implants or as scaffolds for tissue engineered products.
If the design of a hip implant, for instance (Figure 2), is carried out at
nanolevel, it might become possible to construct an implant which closely
mimics the mechanical properties of human bone, preventing stress-shielding and
the subsequent loss of surrounding bone tissue2 . Extra-cellular matrix (ECM)
provides an excellent three-dimensional web of intricate nanofibers to support
cells and present an instructive background to guide their behaviour. It takes
a variety of forms in different tissues and at different stages of development
in the same tissue. This diversity arises through combinations of specific
molecular interactions and geometrical arrangements of collagens, elastins,
proteoglycans, and adhesion proteins, such as fibronectins and laminins.
Unwnding the fibers of ECM, reveals a level of detail unmatched outside the
biological world. Each fiber hides clues that pave the way for cells to form
tissues, as complex as bone, liver, heart and kidney. A key challenge is to
capture the degree of complexity that is needed to functionally replicate the
ECM of natural tissue. Nevertheless, we are still a long way from recreating
the molecular architecture of the ECM and the dynamic mechanisms by which
information is revealed in response to challenges within the local environment.
Nanostructuring of materials provides a powerful mechanism to encourage and
direct cell behaviour, ranging from cell adhesion to gene expression, thus
enhancing their biocompatibility, by dictating the desirable interactions
between cells and materials. The question of how cells detect and respond to
nanofeatures is unresolved yet. However, there are early findings, where the
promotion of one cell type over another, such as osteoblasts (bone-forming
cells) over osteoclasts (bone-resorbing cells), to stimulate bone growth, will
be important in reducing aseptic loosening and failure of implants. It has been
found that not only the scale of topography (5 nm to micrometer scale)
modulates cell behaviour, but also the type of ordered topography (e.g.,
ridges, steps, grooves, pillars, and pits) and even their symmetry (e.g.,
orthogonal or hexagonal packing of nanopits) 32. Furthermore, surface
modifications at nanolevel of biomaterials or their coatings might greatly
enhance the biocompatibility by favouring the interaction of living cells with
the biomaterial, especially by their beneficial effect on cell adhesion and
proliferation. Together with the control of nanoporosity allowing
vascularisation and the growth of cells inside the biomaterial, the
nano-structured surfaces of biomaterials also allow the creation of novel types
of scaffolds for tissueengineered products2 . Nanotechnology in Cardiology:
Nanotechnology has various applications in the field of cardiology research not
only for diagnostic but also for therapeutical purposes14. On the therapeutical
scope, minimally invasive treatments for heart disease, diabetes and other
diseases is a desirable goal for scientists, and there is hope for it, because
of the use of nanotechnology. More precisely, a team led by Paul Grayburn of
Baylor University Medical Center, and Ralph Shohet of the University of Texas
Southwestern Medical School, in Dallas, Texas, has demonstrated that
ultrasound-targeted microbubble destruction (Figure 8) can deliver genes that
stimulate the growth of new blood vessels in rat heart.
Cardiovascular gene therapy could be realized roughly as follows:
identification of a protein whose presence causes blood vessels to form,
production and packaging of strands of DNA that contain the gene for making the
protein and deliverance of the DNA to heart muscle. Of those steps, the last is
the most challenging. In the late 1990s, physicians and physicists hit on the
idea of using ultrasound contrast agents to deliver DNA, which can be seen in
Figure 8. If the ultrasound is intense enough, the bubbles can burst with
sufficient force to breach the membranes of nearby cells. And if the bubbles
are coated with DNA, their destruction releases the DNA, enabling it to enter
the cells through the holes forced open by the burst.
“Biobots” (a kind of nanorobots), another
application of nanotechnology, is the creation of muscle-powered nanoparticles
having the ability to transfer information into cells, gives the potential of
replacing lost biological function of many tissues such as sinoatrial node.
This effect can lead to treatment of diseases which otherwise would be fatal or
difficult to cure for human beings
Nanotechnology against Cancer:
Nanotechnology may have an impact on the key
challenges in cancer diagnosis and therapy. Diagnosing, treating, and tracking
the progress of therapy for each type of cancer has long been a dream among
oncologists, and one that has grown closer thanks to parallel revolutions in
genomics, proteomics and cell bio1ogy. Nanotechnology’s greatest advantage over
conventional therapies may be the ability to combine more than one function.
Recently, there is a lot of research going on to design novel nanodevices
capable of detecting cancer at its earliest stages, pinpointing it’s location within
the human body and delivering chemotherapeutic drugs against malignant cells.
The major areas in which nanomedicine is being developed in cancer involve: a)
early detection of tumour (developing “smart” collection platforms for
simultaneous analysis of cancer-associated markers and designing contrast
agents that improve the resolution of tumour area comparing with the nearby
normal tissues), and b) cancer treatment (creating nanodevices that can release
chemotherapeutic agents). Tumour diagnostics and prevention is the best cure
for cancer, but failing that, early detection will greatly increase survival
rates with the reasonable assumption that an in situ tumour will be easier to
eradicate than one that has metastasized. Nanodevices and especially nanowires
can detect cancer-related molecules, contributing to the early diagnosis of
tumour. Nanowires having the unique properties of selectivity and specificity,
can be designed to sense molecular markers of malignant cells. They are laid
down across a microfluidic channel and they allow cells or particles to flow
through it. Nanowires can be coated with a probe such as an antibody or
oligonucleotide, a short stretch of DNA that can be used to recognize specific
RNA sequences. Proteins that bind to the antibody will change the nanowire’s
electrical conductance and this can be measured by a detector. As a result,
proteins produced by cancer cells can be detected and earlier diagnosis of
tumour can be achieved. Nanoparticle contrast agents are being developed for
tumor detection purposes. Labeled and non-labeled nanoparticles are already
being tested as imaging agents in diagnostic procedures such as nuclear
magnetic resonance imaging24. Such nanoparticles are paramagnetic ones,
consisting of an inorganic core of iron oxide coated or not with polymers like
dextran. There are two main groups of nanoparticles: 1) superparamagnetic iron
oxides whose diameter size is greater than 50 nm, 2) ultrasmall
superparamagnetic iron oxides whose nanoparticles are smaller than 50nm25.
Moreover, quantum dots being the nanoscale crystals of a semiconductor material
such as cadmium selenide, can be be used to measure levels of cancer markers
such as breast cancer marker Her-2, actin, microfibril proteins and nuclear
antigens26. Tumour treatment can be succeeded with nanoscale devices (such as
dendrimers, silica-coated micelles, ceramic nanoparticles, liposomes). These
devices can serve as targeted drug-delivery vehicles capable of carrying
chemotherapeutic agents or therapeutic genes into malignant cells. As an
example, a nanoparticle-based drug called “Abraxane”, consisting of paclitaxel
conjunctive to protein albumin particles, was approved by the Food and Drug
Administration for breast cancer treatment a year ago27. It is worthwhile to
mention that selective delivery and targeting of nanoparticles to tumours may
overcome the problem of toxicity and may increase the effectiveness of drug
delivery. The barriers involving this procedure and that should be under
consideration, are a variety of physical and anatomical characteristics of
solid tumours, such as the necrotic core with the surrounding hypoxic area, the
elevated local temperature and the interstitial liquid pressure. The vascular
permeability of the tumour influence the retention of intravenously
administered nanoparticles, and the subsequent nanoparticle drug-delivery are
shown in Figure 1514,28,29. Several approaches have been used to target
nanoparticles to tumour-associated antigens, including direct conjugation of
nanoparticles to monoclonal antibodies, modified plasma proteins or viral
vectors. Recent progress has been made with targeted viral vectors for gene
therapy applications. Figure 16 demonstrates a nanoparticle-delivered EGFP gene
(gene coding for Enhanced Green Fluorescent Protein) (green) expressed in a
nerve cell (red).
Conclusions
Nanotechnology in modern medicine and nanomedicine is in infancy, having
the potential to change medical research dramatically in the 21st century.
Nanomedical devices can be applied for analytical, imaging, detection,
diagnostic and therapeutic purposes and procedures, such as targeting cancer,
drug delivery, improving cell-material interactions, scaffolds for tissue
engineering, and gene delivery systems, and provide innovative opportunities in
the fight against incurable diseases.Thanks to nanotechnology tools and
techniques, there has been a huge progress on understanding the function of
biological structures and their interaction and integration with several
non-living systems, but there are still open issues to be answered, mainly
related to biocompatibility of the materials and devices which are introduced
into the body. Many novel nanoparticles and nanodevices are expected to be
used, with an enormous positive impact on human health. The vision is to
improve health by enhancing the efficacy and safety of nanosystems and
nanodevices. In addition, early diagnosis, implants with improved properties,
cancer treatment and minimum invasive treatments for heart disease, diabetes
and other diseases are anticipated. In the coming years, nanotechnology will
play a key role in the medicine of tomorrow providing revolutionary
opportunities for early disease detection, diagnostic and therapeutic
procedures to improving health and enhancing human physical abilities, and
enabling precise and effective therapy tailored to the patient.
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