Biomedical Engineering Reference
In-Depth Information
gold electrode by using 1,6-Hexanedithiol as a medium. To quantify the
amount of thrombin, changes in the interfacial electron transfer resis-
tance (Ret) of the aptasensor were monitored using the redox couple of an
[Fe(CN)6]
3−/4−
probe. h e plot of (Reti−Ret0 )/Ret0 against the logarithm
of thrombin concentration is linear with over the range from 0.1 nM to 30
nM with a detection limit of 0.013 nM. h e results were compared with
that of bare electrode with no AuNPs on it. It was observed that the total
amount of aptamer probes immobilized on the gold nanoparticle surface
is sixfold higher than that on the bare electrode. Interference studies were
also conducted and as a result it was found that prepared aptasensor also
showed good selectivity for thrombin without being af ected by the pres-
ence of other proteins [105].
3.3 Conclusion
It is important to have precise, practical, economical and robust devices for
a disease diagnosis. Biosensors can cover these requirements. Introducing
AuNP in these sensors increases sensitivity and provides a better environ-
ment for biological component immobilization. Because of these advan-
tages, the development of various coni gurations of these systems are still
in progress.
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