Biomedical Engineering Reference
In-Depth Information
Remove
template
TEOS
Est-Si
Rebind
1
2
3
Figure 12.32
Scheme for the synthesis of (a) CNTs@Est-MIPs. (1) h e surface of purii ed
CNTs was converted to a silica shell by a sol-gel process using TEOS and APTES in the
presence of CTAB to give core@shell CNTs@SiO2. (2) h e CNTs@SiO2 reacted with
Est-Si to produce a silica surface functionalized with estrone-imprinted polymer. (3) At er
removing estrone by a simple thermal reaction, estrone-imprinted polymer coated CNTs
were obtained [71].
were obtained using a semi-covalent imprinting strategy, which employed
a thermally reversible covalent bond at the surface of silica-coated CNTs
for large-scale production (Figure 12.32). h e adsorption properties were
demonstrated by equilibrium rebinding experiments and Scatchard analy-
sis. h e results demonstrate that the imprinted nanocomposites possess
favorable selectivity, high capacity and fast kinetics for template molecule
uptake, yielding an adsorption capacity of 113.5μmol/g. h e synthetic pro-
cess is quite simple, and the dif erent batches of synthesized CNTs@Est-
MIPs nanocomposites showed good reproducibility in template binding.
h e feasibility of removing estrogenic compounds from environmental
water using the CNTs@Est-MIPs nanocomposites was demonstrated using
water samples spiked with estrone.
12.2.2 h
in-Film Imprinting
A thin i lm is a layer of material ranging from fractions of a nanometer
(monolayer) to several micrometers in thickness. A familiar application of
thin i lms is the household mirror, which typically has a thin metal coating
on the back of a sheet of glass to form a rel ective interface. h e process of
silvering was once commonly used to produce mirrors. Several imprinted
thin i lms of nanometer thickness were also reported in the literature.
Recently, screen-printed electrodes were modii ed with MWCNTs and
molecularly imprinted membranes (MIM) were directly synthesized on
these modii ed electrodes using the
in-situ
thermal polymerization tech-
niques [72]. h e sensing system was easily established by connecting the
