Biomedical Engineering Reference
In-Depth Information
open up avenues to develop smart medical devices that respond to specii c physi-
ological conditions.
By integrating the advantages of biomolecules with unique capabilities of NPGs
such as biocompatibility and high surface activity, biomolecule functionalized
nanoporous i lms (BM-NPG) can open the path to sophisticated design solutions
for present scientii c problems. h e possibilities provided by BM-NPGs are enor-
mous, and some emerging applications include diagnosis and sensing.
Keywords:
Nanomaterials, bioconjugation, nanoporus gold, electrochemical biosensor
11.1 Introduction
New materials are looked at for applications in many i elds of modern
technologies, including sensing, diagnostics, optics and electronics [1]. By
taking the advantages of nanotechnology, such innovations signii cantly
proi t from the access to nanostructured materials with unique proper-
ties resulting from the size reduction. According to the specii c needs of
the application, by changing the size, the chemical, optical, and mechani-
cal behavior can be manipulated. It is expected that the widespread range
of applications of such “nanomaterials” will gradually increase [2]. h ese
materials have good electrical conductivity and consist of oriented, well-
dei ned or random pore morphology. An important feature of the reduced
length scale is the dramatically increased surface, resulting in a large sur-
face-to-volume ratio [1]. In numerous applications, especially those in
the i eld of chemical sensing, when the goal is improving the sensitivity
and lowering detection limits, such high surface areas are worthwhile. h e
increased surface area has many advantages; for instance, in electroana-
lytical chemistry it can lead to a larger amount of an immobilized reagent
on the surface, resulting in larger Faradaic currents. Some advantages of
larger electrode area are better S/N ratios, higher sensitivity, and lower
detection limits [3].
Signii cant progress in the i eld of nanotechnology using gold nano-
structures has been observed in the last decade. Nanoporous materials,
as new types of nanostructures, are a class of high-surface-area materi-
als that due to a wide range of intriguing physical and chemical prop-
erties and diverse applications have recently deserved special attention
[1, 4-7]. h ey have a three-dimensional (3D) spongy architecture with
tunable nanometer pore sizes [8]. Recently, dif erent nanoporous met-
als, such as platinum, copper, gold and… [4] have been applied for a
vast range of applications. Among the various porous metals, nanopo-
rous gold (NPG) has stimulated extensive research enthusiasm because
