Biomedical Engineering Reference
In-Depth Information
Acid treatment
Polymerization
on MWCNT surface
Remove template
Cast on GCE
Template
GCE
MWCNT
MIP network
Figure 12.26
Simplii ed sketch for the construction of MIPCNT on GCE [61].
aqueous, blood serum, and pharmaceutical samples (LOD 0.0186 nmol
L
−1
, S/N=3), by dif erential pulse anodic stripping voltammetry.
In another approach, a sensitive electrochemical sensor was fabricated
for allopurinol (AP) based on immobilization of MIP onto the surface of
MWCNTs which was later on cast onto glassy carbon electrode (GCE)
[61]. h e near equilibrium time to adsorb AP on the surface of electrode
is about 9 min (Figure 12.26). h e modii ed electrode was used to detect
the concentration of AP with a linear range and detection limit (S/N=3) of
0.01-1.0μM and 6.88 nM, respectively. Finally, the modii ed electrode was
successfully applied to determine AP in the human serum sample and two
brand tablets.
12.2.1.9 TiO
2
Nanotubes
During recent decades, fascinating inorganic semiconductor titanium
dioxide (TiO
2
) has attracted extensive attention in the photocatalytic area
for decomposition of organic compounds, sterilization, cancer treatment,
etc., due to its good stability and photochemical activity. Recently, Wang
et al.
proposed a MIP thin i lm for photoelectrochemical (PEC) sensing
of lindane molecules constructed by electropolymerizing o-phenylene-
diamine (o-PD) monomer and lindane template molecule on titanium
dioxide nanotubes [62]. h e resulting PEC sensors were characterized by
scanning electron microscopy, ultraviolet (UV)-Vis spectra and electro-
chemical impedance spectra (Figure 12.27). Under visible light irradia-
tion, MIP i lm can generate the photoelectric transition from the highest
occupied molecular orbital to the lowest unoccupied molecular orbital,
delivering the excited electrons to the conduction band of titanium dioxide
