Biomedical Engineering Reference
In-Depth Information
hybridization were obtained depending on the duplex length (30, 21 and
14 base pairs). Target ssDNA could be determined in the concentration
range from 1 pM to 10 nM, which suggested that this GO-LAPS-based
platform could be considered as a sensitive means for short-chain ssDNA
detection. h is GO-modii ed LAPS sensor could also be extended to other
kinds of biological detection, such as DNA-targeted drugs, tumor markers
or single cells.
h ese recent developments in nanobiosensors and their applications in
biology, especially in medical diagnostics, encompass the concepts of coor-
dinated nanobiosensors integrating the desirable properties of the individ-
ual components: protein machinery for specii city, and the nanoelectrodes
for enhancing sensitivity in electronic detection. Moreover, the utilization
of these biological molecules in conjunction with nanostructured materi-
als has opened the possibility to develop several types of promising bio-
sensors such as nanostructured and miniaturized devices, and implantable
biosensors for real-time monitoring. h e advances discussed clearly dem-
onstrate the considerable growth experienced by electrochemical biosen-
sor technology in terms of applicability and complexity of devices due to
the utilization of electrodes modii ed with nanostructured materials in
order to increase the power detection of specii c molecules, and the devel-
opment of new methodologies for biomolecules immobilization. A great
number of the highlighted applications for the enzyme-based nanobiosen-
sors have focused on glucose sensing using GOx, due to the importance
of diagnosing and managing diabetes. h e most common issue associated
with glucose sensors is slow electron transfer to the electrode at er glucose
oxidation due to inhibition of l avin adenine dinucleotide (FAD) cofactors,
which form the redox center of GOx, by the protective glycoprotein shell.
Graphene and ZnO nanostructured-based sensor platforms have proved
to be advantageous in glucose detection using GOx because of the rapid
response and the potential for miniaturization [1]. When extrapolated,
these advantages have been proven for the detection of other biomedically
important analytes (glutamate, cholesterol, urea, NADH, ethanol, L-lactic
acid, DA, H
2
O
2
, NaNO
2
) by functionalization with the appropriate enzyme.
Currently, research in this area is conducted not only for the construc-
tion of faster, cheaper and more ei cient miniaturized devices, but also
for the increasing integration of electronic and biological systems. h is
way, the future development of highly sensitive and specii c biosensors and
devices will require the combination of multidisciplinary areas like quan-
tum chemistry and solid-state and surface physics, bioengineering, biol-
ogy and medicine, electrical engineering, among others. Advances in any
of these i elds will drastically revolutionize future biomedical diagnostics
