Buffer Selection Recommendation
| |
Buffer |
pH range |
UV range, nm |
|
|
TFA |
1.5-2.5 |
>210 |
+ |
|
Acetic acid |
3.5-5.0 |
>220 |
++ |
|
Formic acid |
2.5-4.0 |
>220 |
++ |
|
H2SO4 |
1.0-2.5 |
>195 |
+- |
|
HClO4 |
1.5-2.5 |
>195 |
- |
|
H3PO4 |
1.5-3.0 |
>195 |
-- |
|
TEA phosphate |
1.8-3.1 |
>195 |
-- |
|
Sodium Phosphate |
1.8-3.1 |
>195 |
-- |
| |
|
6.0-7.0 |
>195 |
-- |
|
Ammonium Phosphate |
1.8-3.1 |
>195 |
-- |
|
TEA Formate |
2.5-4.0 |
>220 |
+ |
|
TEA Acetate |
3.5-5.0 |
>220 |
+ |
|
Ammonium Formate |
2.5-4.0 |
>220 |
++ |
|
Ammonium Acetate |
3.5-5.0 |
>220 |
++ |
Physical Properties of Acids Useful in HPLC Application
| |
Name |
Formula |
F.W. |
Density, g/ml |
Boiling point, oC |
UV range, nm |
Ion strength of 0.1% solution, mM |
pH of 0.1% solution |
| |
Sulfuric acid |
H2SO4 |
98.08 |
1.840 |
high |
>195 |
20 |
2.0 |
| |
Perchloric acid |
HClO4 |
100.46 |
1.664 |
high |
>195 |
20 |
2.0 |
| |
Phosphoric acid |
H3PO4 |
98.00 |
1.685 |
high |
>195 |
15 |
2.1 |
| |
Trifluoroacetic acid (TFA) |
CF3COOH |
115.03 |
1.493 |
75 |
>210 |
20 |
2.0 |
| |
Methanesulfonic acid |
CH3SO3H |
96.11 |
1.481 |
high |
>195 |
20 |
2.0 |
|
Formic acid |
HCOOH |
46.03 |
1.220 |
100 |
>220 |
2 |
3.0 |
|
Acetic acid |
CH3COOH |
60.05 |
1.049 |
117 |
>220 |
0.2 |
4.0 |
|
