Biomedical Engineering Reference
In-Depth Information
4.
Nanomedicine and nanotechnology
Nanotechnology is a collective definition referring to every technology and
science which operates on a nanoscale and refers to the scientific principles
and new properties that can be found and mastered when operating in
this range. When we bring materials down to the nanoscale, the properties
change and nanoparticles have other optical, magnetic or electrical prop-
erties than larger particles. These properties are and will be utilized in a
wide spectre of areas as in medical applications, information technologies,
energy production and storage, materials, manufacturing, instrumentation,
environmental applications and security. Nanotechnology in biomedical re-
search has emerged as an interdisciplinary science that has quickly found
its own niche in clinical methodologies including imaging, diagnostic and
therapeutic. The nano-based technology is expected to expand multi-
directionally to provide unmet needs in medicine and has potential to gen-
erate innovations that will bring breakthrough treatments to various human
diseases, including cancer. Nanotechnology is characterized by the manipu-
lation of atoms and molecules leading to the construction of structures in
the nanometer scale size range [26-27]. The National Institute of Health
defines nanomedicine as the application of nanotechnology to diseases treat-
ment, diagnosis, monitoring, and to the control of biological systems. The
field of nanomedicine aims to use the properties and physical characteristics
of nanomaterials, which have been extensively investigated as novel intra-
vascular or cellular probes, for both diagnostic and therapeutic purposes.
The sub-micron size of nanoparticle systems confers considerable advan-
tages as compared to large sized systems including targeted delivery, higher
and deeper tissue penetrability, greater cellular uptake and greater ability to
cross the BBB [28]. NPs consist of molecules with dimensions in the order
of 10
-9
nm, of different kind and compositions capable of containing drugs
and DNA-RNA fragments and able to regulate their transport and intake
into target tissues and cells. NPs show some peculiar features, such as their
surface to mass ratio, which is higher than that of other particles, their quan-
tum properties, and their capacity to transport other compounds [29-30].
Nanomedicine is applied in many fields of biology and medicine, such as
fluorescent biological labels, drug and gene delivery, detection of pathogens,
detection of proteins, probing of DNA structure, tissue engineering, tumor
destruction via heating, separation and purification of biological molecules
and cells, MRI contrast enhancement, and phagokinetic studies [31]. NP
drug delivery vehicles have shown the ability to encapsulate a variety of ther-
apeutic agents such as small molecules (hydrophilic and/or hydrophobic),
peptides, protein-based drugs, and nucleic acids (Figure 4-1). By encapsu-
lating these molecules inside a nanocarrier, the solubility and stability of
the drugs can be improved, providing an opportunity to reevaluate potential
drugs previously ignored because of poor pharmacokinetics. Encapsulated
