Biomedical Engineering Reference
In-Depth Information
Adequate
removal
Distortion of
the binding
points
Incomplete
removal
Collapse of
the cavity
after removal
Rupture of
the cavity
during
removal
Figure 11.3
Diagrammatic representation of the changes induced in the MIPs during the
removal of the template [Co-opted from reference 9 with permission].
1. Distortion of binding sites due to extreme treatment of poly-
mer with washing solvent.
2. Collapse of binding site due to removal of template from
polymer matrix.
3. Rupture of cavity during removal i.e. some part of polymer
may get dissolved due to solvent used for washing.
11.1.4
How to Overcome the Problems
To overcome these problems, recently, nanotechnologies and surface chem-
istry are introduced into molecular imprinting strategy. Nanostructured,
imprinted materials have a small dimension with extremely high surface-to-
volume ratio, so that most of template molecules are situated at the surface
and in the proximity of materials surface (Figure 11.4). Figure 11.4 illustrates
the distribution of ef ective binding sites in the imprinted bulky materials and
imprinted nanoparticles (NPs) at er the extraction of templates is done [10].
We assume that these templates located within x-nanometers from the
surface can be removed in the bulky materials with a scale of d, and the
resultant imprinted sites can be accessed to target species. h e ef ective vol-
ume of imprinted materials that can rebind target species is [d3-(d-2x)3].
In general, the x value is very small for highly cross-linked bulky materials
