Biomedical Engineering Reference
In-Depth Information
glycolipid molecules were inserted into dodecanethiol by physical insertions.
Guo et al.
(2007)
state that the recognition between Con A and carbohydrate was observed by UV-vis
spectrophotometry. They state that there is an additional monolayer (i.e., alkylthiol), which
is used to tether the reporter (i.e., glycolipid) monolayer and the transducer (i.e., Au colloids).
The detection limit for Con A by the biosensor was 0.1 nM.
Figure 12.9a
shows the binding and dissociation of 0.1 nM Con A in solution to the gold
nanoparticle biosensor (
Guo et al., 2007
). A dual-fractal analysis is required to adequately
describe the binding kinetics. A single-fractal analysis is adequate to describe the dissociation
kinetics. The values of (a) the binding rate coefficient,
k
, and the fractal dimension,
D
f
, for a
single-fractal analysis, and (b) the binding rate coefficients,
k
1
and
k
2
, and the fractal
dimensions,
D
f1
and
D
f2
, for a dual-fractal analysis are given in
Table 12.5
.
It is of interest to note that as the fractal dimension increases by a factor of 2.5438 from a
value of D
f1
equal to 1.0 to D
f2
equal to 2.5438, the binding rate coefficient increases by a
factor of 2.526 (almost a linear increase) from a value of
k
1
equal to 1.0 to
k
2
equal to
10
7
6
8
5
6
4
3
4
2
2
1
0
0
0
10
20
30
Time (min)
40
50
60
0
10
20
30
Time (min)
40
50
60
A
B
25
20
15
10
5
0
0
10
20
30
Time (min)
40
50
60
C
Figure 12.9
Binding of different concentrations (in nM) of Con A to a colloidal gold coated with glycolipid/
dodecanethiol bilayer (
Guo et al., 2007
): (a) 0.1, (b) 1.2, (c) 4.8.
