Biomedical Engineering Reference
In-Depth Information
shows good stability and acceptable reproducibility for the determination
of MNZ. Under optimal experimental conditions, the current response of
the electrochemical sensor was linear to MNZ concentrations in the range
from 5.0×10
-8
to 1.0×10
-6
M, with the detection limit of 1.6×10
-8
M. h e
method was successfully applied to the analysis of MNZ in milk samples
and honey samples with acceptable recoveries of 93.5% to 102.2%.
Similarly, Ma
et al.
prepared core-shell molecularly imprinted polymers
of 17β-estradiol on the surface of silica nanoparticles (SiO
2
@E2-MIPs)
[40]. h e sorption capacity of the SiO
2
@E2-MIPs were nearly 5 times that
of the NIPs, and it only took 25 min to achieve the sorption equilibrium.
h is indicated that the SiO
2
@E2-MIPs exhibited a high selectivity, large
adsorption capacity and fast kinetics. When the SiO
2
@E2-MIPs were used
as dispersive solid-phase extraction absorbents to selectively enrich and
determine estrogens in duck feed, the average recoveries of E2 and estriol
(E3) were higher than 96.74% and 72.07%, respectively, and the relative
standard deviations (RSD) of E2 and E3 were less than 1.61% and 3.28%,
respectively. h e study provides an ef ective method for the separation
and enrichment of estrogens in the complex matrix samples by the SiO
2
@
E2-MIPs.
In general, SiO
2
-based core shell nanoparticles are more preferable and
have been reported on a lot, but some core-shell gold nanoparticles are also
reported as a substrate for imprinting. In the year 2013, Xue
et al.
explored
surface-imprinted core-shell AuNPs for the highly selective detection of
BPA by SERS [41]. A triethoxysilane-template complex (BPA-Si) was syn-
thesized and then utilized to fabricate a MIP layer on the AuNPs via a sol-
gel process (Figure 12.15).
Imprinting
Remove
template
MIP-AuNPs
BPA-Si
TEOS
Raman Probe
MIP-ir-AuNPs
Rebind
Portable Raman
Spectrometer
MIP-ir-AuNPs incubated in BPA
600
1000
1400
Raman Shift (cm
-1
)
Figure 12.15
Schematic illustration for fabricating MIP-ir-AuNPs and using MIP-ir-
AuNPs for selective detection of BPA using a small portable Raman spectrometer [41].
