Biomedical Engineering Reference
In-Depth Information
Introduction
14.1
h e development of nanoparticles for drug delivery began in the1960s [1].
Recent developments in multifunctional nanoparticles has of ered a great
potential for targeted delivery of drugs for treatment of various types of
diseases. Nanoparticles are basically solid colloidal particles ranging in
size from 1 to 1000nm (μm). Nanoparticles are made from biocompat-
ible and biodegradable materials such as polymers, either natural (e.g.
gelatin, albumin) or synthetic (e.g. polylactide, polyalkylcyanoacrylates)
or solid lipid nanoparticles [2]. h e drug loaded in nanoparticles is usu-
ally released from the matrix by dif usion, swelling, erosion or degrada-
tion. h e reason, why nanoparticles used for medical purposes is large
surface to mass ratio which is much larger than other particles. Large
surface area provides ability to bind, adsorb and carry other compounds
such as drugs, proteins, probes. h ey consist of macromolecular materials
in which active agent (drug or biologically active material) is dissolved,
entrapped, encapsulated or to which active agent adsorbed or attached [3].
Unfortunately the conventional therapeutic strategies require unnecessar-
ily high systemic administration due to non-specii c biodistribution and
rapid metabolism of free drug molecules before reaching their targeted
sites. h erefore nowadays nanotechnology based targeting improved the
therapeutic success by limiting adverse drug ef ects and patient requires
less frequent administration regimes, which ultimate results in more
Oral
Routes of
administration
of various
drug delivery
systems
Injectable
Implantable
Inhalable
Figure 14.1
Various Routes of Drug Delivery Systems.
