Biomedical Engineering Reference
In-Depth Information
CD-MWCNTs
Au-PAMAM
CTC-MIP
Rebinding
Removal
Gold electrode
CD
MWCNTs
PAMAM
AuNPs
CTC
CSDT
Figure 11.30
h e preparation of the CD-MWCNTs/Au-PAMAM/MIPs/gold electrode [65].
of 4.954×10
-8
mol/L (0.0255 mg/kg, S/N=3). h e developed sensor showed
high selectivity and excellent stability toward CTC. h e linear range was
found to be from 3.0×10
-8
to 8.0×10
-5
mol/L, with a LOD of 2.7×10
-8
mol/L
(S/N=3) for OTC. h e results from real sample analysis coni rmed the
applicability of the sensor to quantitative analysis.
QDs-based MIP composite nanospheres were successfully prepared
via a facile and versatile ultrasonication-assisted encapsulation method
[67]. Unlike the hydrogen-bond-based MIPs, these so-prepared QDs-
MIP composite nanospheres, relying on the interaction including van
der Waals forces and hydrophobic forces, demonstrated excellent selec-
tivity in aqueous media. h eir small particle sizes and carboxyl-enriched
polymer matrixes give rise to their good dispersibility and stability in
aqueous solution, and faster adsorption and desorption kinetics, which
further make them extensively applicable for chemical/biological sen-
sors in aqueous media. Based on the l uorescence quenching via tem-
plate analytes (diazinon) rebinding into the recognition cavities in the
polymer matrixes, the QDs-MIP nanospheres were successfully applied
to the direct l uorescence quantii cation of diazinon, independent of
extracting templates from the MIP nanospheres, as well as further com-
plicated and time-consuming assays. h is novel method can selectively
and sensitively detect down to 50 ng/mL of diazinon in water, and a lin-
ear relationship has been obtained covering the concentration range of
50-600 ng/mL. h e present studies provide a new and general strategy to
fabricate other multifunctional (luminescent and magnetic) inorganic-
organic MIP nanocomposites with highly selective recognition ability in
aqueous media and are pretty desirable for biomedical/chemical sensing
applications.
