Biomedical Engineering Reference
In-Depth Information
140
4
120
3
100
80
2
60
40
1
20
0
0
2.35
2.4
2.45
2.5
2.55
2.6
2.65
0
0.5
1
1.5
2
2.5
A
B
Fractal dimension, D fd
Fractal dimension, D f
4000
3000
2000
1000
0
0
5
10
15
20
25
30
C
Fractal dimension ratio, D f / D fd
Figure 11.11
(a) Increase in the binding rate coefficient, k, with an increase in the fractal dimension, D f .
(b) Increase in the dissociation rate coefficient, k d , with an increase in the fractal dimension in the
dissociation phase, D fd . (c) Increase in the affinity, K (
k/k d ), with an increase in the fractal
dimension ratio, D f /D fd .
ΒΌ
The fit is reasonable. Only three data points are available. The availability of more data
points would lead to a more reliable fit. Only the positive error is shown in Equation (11.5c ),
since the error is large, and the affinity can only have positive values. The affinity, K , exhibits
an order of dependence between one and a half and two (equal to 1.746) on the ratio of fractal
dimensions, ( D f / D fd ), present on the sensor chip surface.
Uno et al. (2007 ) analyzed the SPR biosensor responses to PNA-DNA hybridization. These
authors used CYP2C9*2 as the probe PNA and the target DNA was complementary
CYP2C9*2 (target DNA2). They used target DNA concentrations in the 0.1-5.0 m M range.
Figure 11.12a shows the binding and the dissociation of 5 m M target DNA concentration in
solution to the probe PNA immobilized on the sensor surface. 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, (b) the binding rate coefficients,
Search WWH ::




Custom Search