Biology Reference
In-Depth Information
Figure 14.14.
Schematic of an electrochemical SNP quantitative assay
based on nanoparticle probe and sequential dna hybridization.
for DNA immobilization resulting in higher probe density and
improved electron transfer to the underlying electrode. The use
of [Co(bpy)
3
]
3
+
-doped Si NPs as labels for electrochemical DNA
detection was reported by Zhu
et al.
[70]. In this work [Co(bpy)
3
]
3
+
molecules were loaded into Si NPs during NP synthesis, and
then conjugated to amine-terminated ssDNA detection probes via
trimethoxysilylpropydiethylenetriamine and glutaraldehyde. This
now electroactive Si NP functionalized detection probe was used
in a sandwich assay format with capture probe DNA immobilized
onto a glassy carbon electrode. The high loading of [Co(bpy)
3
]
3
+
molecules in the Si NPs resulted in a 200 pM target DNA detection
limit. The response from a three-base pair mismatch sequence and
noncomplementary sequencewas negligible.
Recently, Ma and coworkers [71] reported the use of Si NP
films for enhanced electrochemical DNA detection. Si NPs were
