Biomedical Engineering Reference
In-Depth Information
We prefer to carry out numerical integrations of these equations, yielding
the time-domain FID.
Starting conditions for the integration are
M
A
(t~0)~
½
A
eq
,0
M
B
(t~0)~
½
B
eq
,0
ð
10
:
17
Þ
M
C
(t~0)~
½
C
eq
,0
The spectrum is subsequently obtained by Fourier transformation of the
FID.
Inspection of kinetic constants may immediately lead to predictions of slow
and fast exchange, even in case of a complicated mechanism. The rule is that if
two species i and j are connected by a process slower than v
i
{v
j
and if there
is no process 'through' another species available that is faster, that these two
resonances are in slow exchange. In reverse, if such a fast 'detour' path is
available, than fast exchange ensues.
10.2 The Proton Ligands to Inositol Hexakis Phosphate
Take Five Instead of Three Log Units to Complete
Binding
myo-Inositol hexakis phosphate (IP6) is a polyphosphate based on 6-hydroxy
hexane, also known as inositol. The structure is shown in Figure 10.1. IP6 is
Figure 10.1
The structure and
31
P NMR spectrum of inositol hexakis phosphate
(IP6). Five of the six phosphates are, axial, one is equatorial. The NMR
data was recorded at 40 MHz pH 3.5. Adapted from ref. 11.
