CHELATORS AS BUFFERS, cont.

3/8/1999

Under the conditions of: 0.1 N ionic stength, 7.0 pH, 20 C

From BERS.CCM:

Chelator

Kd

HIGH

LOW

ADA

1.56E-04

4.93E-04

4.93E-05

ATP

5.36E-05

1.69E-04

1.69E-05

BAPTA

1.40E-07

4.43E-07

4.43E-08

Citrate

2.99E-04

9.46E-04

9.46E-05

DiBrBapta

1.15E-06

3.64E-06

3.64E-07

EDTA

5.36E-08

1.69E-07

1.69E-08

EGTA

3.68E-07

1.16E-06

1.16E-07

HEDTA

5.13E-06

1.62E-05

1.62E-06

NTA

2.55E-04

8.06E-04

8.06E-05

PO4

1.89E-02

5.98E-02

5.98E-03

SO4

3.72E-02

1.18E-01

1.18E-02

Sorted by Kd:

Chelator

Kd

HIGH

LOW

EDTA

5.36E-08

1.69E-07

1.69E-08

BAPTA

1.40E-07

4.43E-07

4.43E-08

EGTA

3.68E-07

1.16E-06

1.16E-07

DiBrBapta

1.15E-06

3.64E-06

3.64E-07

HEDTA

5.13E-06

1.62E-05

1.62E-06

ATP

5.36E-05

1.69E-04

1.69E-05

ADA

1.56E-04

4.93E-04

4.93E-05

NTA

2.55E-04

8.06E-04

8.06E-05

Citrate

2.99E-04

9.46E-04

9.46E-05

PO4

1.89E-02

5.98E-02

5.98E-03

SO4

3.72E-02

1.18E-01

1.18E-02

Graphed on Log scale, the useful ranges for each chelator become: [FURA2 added for reference]

PLEASE NOTE: PO4 and SO4 are likely to produce precipitates as well.