Biology Reference
In-Depth Information
(A)
Thrombin Lysozyme
Wash
(B)
0.1M HNO
3
(C)
Cd Pb
Cd
2+
& Pb
2+
Figure 2.5.
Schematicrepresentationofthedisplacementassay.(A)Mixed
monolayer of thiolated aptamers on the gold substrate with the bound
protein-QD conjugates (B) Sample addition and displacement of the tagged
proteins (C) Dissolution of the remaining captured nanocrystals followed
by their electrochemical-stripping detection at a coated glassy carbon elec-
trode.
Another aptasensor for the detection of thrombin has been
recentlyreported[30].Itisbasedonasandwichassayandontheuse
ofNPlabels.Inthisworkaninterestingaspectconcernsthecoupling
ofsignalamplificationduetoNPswiththepreparationofananogold
electrode by electrochemical deposition of Au-NPs on a gold elec-
trode. The surface of the gold electrode was pretreated as follows:
heated in a piranha solution for about 5 min, polished with alu-
minaslurries,washedultrasonicallywithwater,driedwithnitrogen
gas, and cycled in 0.5 M H
2
SO
4
aqueous solution scanning between
0.3 and 1.5 V until a stable gold oxide formation/reduction cyclic
