Biology Reference
In-Depth Information
3D-CPNEs
Figure4.6.
SchematicillustrationofthefabricationoftheApt/3D-CPNEs-
based thrombin aptamer sensor [29] (reprinted with permission of the
American Chemical Society).
biosensor where the target DNA was immobilized on AuNPs films
boundtothesurfaceofachitosan-entrappedcarbonpasteelectrode
(CPE). The probe DNA was labeled with CdSe quantum dots, and
the CdSe was loaded on the electrode surface via DNA hybridization
and then dissolved in HNO
3
. The released Cd
2
+
was detected
by differential pulse anodic stripping voltammetry (DPASV). The
dynamic detection range for 18-base DNA specific sequence of the
cauliflowermosaicvirusgenewas5.0
×
10
−
12
to5.0
×
10
−
7
M,with
a detection limitof 6.5
×
10
−
13
M.
Table 4.1 summarizes data reported between 2007 and 2009 for
DNA sensors where the detection strategy is related to the direct
detection of redox markers.
4.3.1.2 Detection based on enzymatic labels
Another detection strategy that takes advantage of the use of Au-
NPs in the immobilization step to improve the immobilization
and orientation of DNA strands is involving enzyme reactions in
the detection process. A nice recent example is the one reported
