Biology Reference
In-Depth Information
Figure 7.15.
SECMimagewithcorrespondingcurrentprofilerecordedfor
a matched and three different mismatched dsDNA microarrays on a gold
substrate in the absence (a) and presence of of Zn
2
+
(b). Please note the
differences in the normalized current as a function of mismatch position,
which is enhanced in the presence of Zn
2
+
.P.M.Diakowski,H.-B.Kraatz,
Chem. Commun
., 2009, 1189-1191. Reproduced by permission of the Royal
Society of Chemistry.
N
-atoms of the purine bases. The
R
ct
of the different metal ions
was found in the order of Ca
2
+
>
Mg
2
+
=
Hg
2
+
>
Cd
2
+
>
Ni
2
+
>
Cu
2
+
Zn
2
+
which is inversely proportional to their free energies
of hydration (see Fig. 7.16) [99].
>
7.3.9
Miscellaneous Methods
Recently, Zhu
et al.
[100] exploited PAMAM dendrimers to tag the
target strand which increase the
R
ct
on hybridization with surface
immobilized capture strand. The
R
ct
can easily distinguish ds-
DNA without PAMAM tag, mismatched and non-complementary
sequences from PAMAM tagged complementary ds-DNA with
picomolar sensitivity (Fig. 7.17).
Watanabe
et al.
[101] detected DNA mismatches through a
strand exchange reaction in which the duplex consisting of a
capture probe and a redox-labeled probe strand are immobilizedon
