Biomedical Engineering Reference
In-Depth Information
CD-MWCNTs
AU-PAMAM
CTC-MIP
Rebinding
Removal
Gold electrode
CD
MWCNTs
PAMAN
AuNPs
CTC
CSDT
Figure 12.30
h e preparation of the CD-MWCNTs/Au-PAMAM/MIPs/gold electrode [65].
(Au-PAMAM) and chitosan derivative (CSDT) for selective and convenient
determination of chlortetracycline (CTC) [65] and oxytetracycline (OTC)
[66]. h e electrochemical sensor was fabricated by stepwise modii cation
of cyclodextrin-CNTs composites (CD-MWCNTs) and Au-PAMAM onto
the gold electrode (Figure 12.30). h e layer of MIPs was the outer layer of
the electrochemical sensor. Herein, CSDT acted as functional monomer,
and CTC or OTC as the template molecule. h e CV and amperometry
were used to characterize the electrochemical behavior of the developed
sensor. h e linear range of the molecularly imprinted sensor was from
9.00×10
-8
to 5.00×10
-5
mol/L (from 0.0464 mg/kg to 25.767 mg/kg), with
the LOD of 4.954×10
-8
mol/L (0.0255 mg/kg, S/N=3). h e developed sen-
sor 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.
h e 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 selectivity
in aqueous media. h eir small particle sizes and carboxyl-enriched poly-
mer matrixes give rise to their good dispersibility and stability in aque-
ous solution, and faster adsorption and desorption kinetics, which further
make them extensively applicable for chemical/biological sensors in aque-
ous media. Based on the l uorescence quenching via template analytes
