Biomedical Engineering Reference
In-Depth Information
brain tumours. The macrophage MRI detection with SPIO of tumor mor-
phology might facilitate the surgical resection or biopsy of brain tumors.
The main goal of nanotechnology in brain tumor imaging is an accu-
rate and early diagnosis without side toxic effects and the evaluation of the
efficacy of non-invasively treatments [5, 77]. These new cellular targeting
based imaging detection methods can reach the specific and selective mo-
lecular recognition only for tumor cells, through the recognition of tumor
specific molecules into ligand-receptor, antibody-antigene interaction, or
other interaction processes between nanoparticle drug-loaded systems and
cancer cells, leading to a diffuse and complete delivering of drug into can-
cer cells [78]. The achievement of higher targeting efficiency per NP will
require the finding of more efficient bio-markers for cancer and correspond-
ing targeting moieties. By detecting and analyzing tumor cells and tissues
with nanotechnologies, the internal biological features of cancer during its
occurrence and development can be revealed. Generally speaking, the ap-
plication of nanotechnology in medical diagnostics can be subdivided into
in vitro diagnostic devices and in vivo
imaging. The improvements in the
technologies to characterize cells or cell compartments in vitro
(optical and
luminescence microscopy, scanning probe microscopy, electron microscopy
and imaging mass-spectrometry) have been important for the development
of nanomedicine. The miniaturization and integration of different functions
in a single device, based on nanotechnology-derived techniques, have led to
a new generation of devices that are smaller and faster, and give accurate
readings. They require much smaller samples, implying less invasive and
traumatic sample extraction methods, and deliver more complete and more
accurate biological data from a single measurement. The use of these de-
vices in research has become routine, and has improved the understanding
of the molecular basis of disease, as well as helping to identify new therapeu-
tic targets. In vitro diagnostic devices mainly include nanobiosensors and
microarrays. The nanobiosensors are systems composed by biological and
biomimetic recognition elements. Interaction between the compound of in-
terest and the recognition element produces a variation of physical-chemical
properties (pH, electron transfer, heat, potential, mass, and optical proper-
ties). Prototype sensors have been successfully used to detect nucleic acids,
proteins and ions. They can operate in liquid or gas phase, opening up an
enormous variety of downstream applications. These detection systems use
inexpensive low-voltage measurement methods and detect binding events
directly [49].
Microarray-based studies have enormous potential in the exploration of
diseases such as cancer, and in the design and development of new drugs.
Microarrays have been widely applied in the study of various pathological
conditions, including inflammation, atherosclerosis, breast cancer, colon can-
cer and pulmonary fibrosis [79]. As a result, functions have been assigned to
previously unannotated genes, and genes have been grouped into functional
