Biology Reference
In-Depth Information
A
3
2.5
Prediction
2
Data
1.5
1
1
8
15
22
29
36
Temperature (C)
B
1.5
1.4
1.3
Prediction
1.2
1.1
1
0.9
Data
0.8
0.7
0
0.05
0.1
0.15
0.2
0.25
0.3
Ionic strength (M)
Fig. 3
EGTA apparent Ca
2
þ
a
Y
nity (K
0
Ca
) is influenced by temperature (A) and ionic strength (B).
The experimental data in A is from
Harrison and Bers (1987)
at pH 7.00 and 0.19 M ionic strength and
in B from
Harafuji and Ogawa (1980)
at pH 6.8 and 22
C. Predicted values are based on the
temperature and ionic strength corrections described in the text.
EGTA a
nity is only reduced by about 30%. In contrast, raising temperature from
1to36
C approximately doubles the apparent a
Y
nity of all three of the Ca
2
þ
Y
bu
V
ers shown in
Figs. 3-5
(i.e., EGTA, BAPTA, and Br
2
-BAPTA).
III. Methods
A. Basic Mathematical Relationships
From the forgoing and the data shown in
Figs. 1 and 3-5
, it is clear that one
needs to know quantitatively how the bu
ers being used are altered by the typical
range of experimental conditions (e.g., pH, temperature, and ionic strength). While
V
