Biomedical Engineering Reference
In-Depth Information
The authors report that their gold nanoparticle nanosensor exhibits a detection limit for
mouse IgG of 100 ag/ml (0.7 attamoles). This according to them is comparable to that
exhibited by the bio-barcode assay (
Nam et al., 2003
), and is of an order of magnitude lower
than that exhibited by cyclic voltametry.
Selvaraju et al. (2007) claim in concluding that they have developed a nanosensor that uses
magnetic beads for a nanocatalyst-based immunoassay. Their sensor exhibits an efficient
immunoreaction and separation along with ultrasensitive detection. Furthermore, their bio-
sensor not only provides a low level of NSB of the IgG-AuN conjugate but also facilitates
the capture of the IgG. Also, the IgG-AuN permit a high signal amplification via the catalytic
reduction of
p
-nitrophenol. Their nanosensor may be used to detect a wide range of con-
centrations in a single assay format.
5.12 Conclusions
Examples of nanobiosensors that have recently appeared in the open literature and those that
have been recently presented in a couple of conferences have been presented here, as well as
some that have recently appeared in the recent literature. As indicated earlier, the examples
were selected at random, and those that were briefly analyzed may be classified into three
board categories depending on the analyte detected, as shown below:
(a) Medical Applications
Cancer
Jokerst et al. (2009)
Glucose
Liu et al. (2009)
PSA
Nagatani et al. (2006)
Reactive oxygen species
Henderson et al. (2009)
Autoantibodies
Drouvalakis et al. (2008)
(b) DNA/RNA Applications
DNA/RNA
Li et al. (2009)
Viral RNA
Sha et al. (2007)
(c) Other Applications
Antigen-antibody binding
Olkhov and Shaw (2008)
Electrochemical immunosensing
Selvaraju et al. (2007)
These examples provide a perspective of the different nanotechnology techniques and pro-
cesses that have been recently used to develop effective nanobiosensors. It should be
emphasized that the examples were selected at random, and the brief classification presented
above may not be a “complete picture” of the different categories where nanobiosensors are
