Biomedical Engineering Reference
In-Depth Information
5 Synthesis of Colloidal Nanoparticles . . .................................................... 241
6 Different Types of Nanoparticles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ........................ 241
6.1 Functionalized Nanoparticles ........................................................ 241
6.2 Functionalized Carbon Nanotubes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 247
6.3 Metal Nanoparticles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248
6.4 Semiconductor Nanoparticles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 253
6.5 Magnetic Nanoparticles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 256
6.6 MR Contrast Agents . . ................................................................ 260
6.7 Lanthanide-Based Nanoparticles . .................................................... 265
7 Targeted Drug Delivery Using Nanoparticles . . . . . . . . ..................................... 266
7.1 Passive Targeting by Nanoparticles .................................................. 266
7.2 Active Targeting by Nanoparticles .................................................. 266
7.3 Drug-Infused Nanoparticles Stop Cancer from Spreading . . . . . . . . .................. 270
7.4 Mechanism of Nanoparticle Internalization ......................................... 271
8 Conclusion and Future Prospects . . ........................................................ 272
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 272
1
Introduction
In the past, use of nanoparticles has been made without knowledge of their
existence, and we now find that the particles used were in the nanoregime.
Nanoparticles were used by artisans as far back as the ninth century in
Mesopotamia for generating a glittering effect on the surface of pots. These
nanoparticles were created by the artisans by adding copper and silver salts and
oxides, together with vinegar, ochre and clay, onto the surface of previously glazed
pottery.
The last few decades have seen the emergence of nanomaterials for several
applications in almost all fields of life, ranging from solid state lighting to biomedi-
cal applications [
1
,
2
]. Their properties lie between those of the bulk material and
those of atoms as they are only made up of some atoms arranged in an ordered
fashion. The small size of these nanoparticles gives them significantly different
properties, which in turn result in the widespread applications of these
nanomaterials. Various nanoscale materials, such as nanorods, nanowires [
3
],
nanotubes, and nanofibers [
4
], have been explored in many biomedical applications
[
5
] because of their novel properties, such as the high surface-to-volume ratio,
surface tailorability, and multifunctionality. Transmission electron microscopic
(TEM) images of plasmonic gold nanostructures such as nanospheres, nanorods,
and nanoshells are shown in Fig.
1
.
For biomedical applications, nanomaterials have been widely used in the field of
tissue engineering, for diagnosis and treatment of certain diseases such as cancer,
and for other biomedical applications include targeted drug delivery and imaging,
hyperthermia, magneto-transfections, gene therapy, stem cell tracking, molecular
and cellular tracking, magnetic separation technologies (e.g., rapid DNA sequenc-
ing), and detection of liver and lymph node metastases. The most recent
applications of superparamagnetic iron oxide nanoparticles (SPIONs) are in early
detection of cancer, atherosclerosis, and diabetes.
