Biomedical Engineering Reference
In-Depth Information
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 11.15
Schematic illustration for fabricating MIP-ir-AuNPs and using MIP-ir-
AuNPs for selective detection of BPA using a small portable Raman spectrometer [41].
within which abundant amine groups were generated. The rebinding
kinetics study showed that the MIP-ir-AuNPs could reach the equi-
librium adsorption for BPA within 10min owning to the advantage
of ultrathin core-shell nanostructure. Moreover, a linear relationship
between SERS intensity and the concentration of BPA on the MIP-ir-
AuNPs was observed in the range of 0.5 -23 22.8 mg/L, with a LOD
of 0.12 mg/L.
Similarly Du
et al.
also reported a core-shell composite of AuNPs and
SiO
2
molecularly imprinted polymers (AuNPs@SiO2-MIPs) through sol-
gel technique and applied as a molecular recognition element to construct
an electrochemical sensor for determination of dopamine [42]. Compared
with previous imprinting recognition, the main advantages of this strat-
egy lie in the introduction and combination of AuNPs and biocompatible
porous sol-gel material (SiO
2
) (Figure 11.16). h e template molecules were
i rstly adsorbed at the AuNPs surface due to their excellent ai nity, and
subsequently they were further assembled onto the polymer membrane
through hydrogen bonds and p-p interactions formed between template
molecules and silane monomers. CV was carried out to extract dopamine
molecules from the imprinted membrane, and as a result, dopamine could
be rapidly and ef ectively removed. h e prepared AuNPs@SiO
2
-MIPs sen-
sor exhibited not only high selectivity toward dopamine in comparison to
other interferents, but also a wide linear range over dopamine concentra-
tion from 4.8×10
-8
to 5.0×10
-5
M with a detection limit of 2.0×10
-8
M (S/
N=3). Moreover, the new electrochemical sensor was successfully applied
to the dopamine detection in dopamine hydrochloride injection and
human urine sample.
