Although the instrument corrects the compressibility to suppress pulse increase caused by the effect of the compressibility of the solvent, setting a compressibility suitable for the solvent used enables more accurate correction.
Input the compressibility (GPa)-1 with the numeric keypad and press [Enter]. The initial value is 0.45.
| Mobile Phase |
Compressibility (GPa)-1 |
| Water |
0.45 |
| Acetonitrile |
1.20 |
| Methanol |
1.25 |
| Ethanol |
1.20 |
| 2-propanol |
1.20 |
| Hexane |
1.60 |
| Heptane |
1.25 |
| Cyclohexane |
1.25 |
| Ethyl Acetate |
1.10 |
| Chloroform |
1.10 |
| Benzence |
1.00 |
· Single solvent
Set the compressibility according to the table.
· Mixture of water and organic solvent
If the concentration of the organic solvent is 50% or less, "0.45" is recommended for the compressibility of water. If the concentration is more than 50%, make the value closer to the compressibility of organic solvent according to the mixture ratio.
Example) When the ratio between water and acetonitrile is 50 : 50, set "0.45". When the ratio between water and acetonitrile is 30 : 70, set "0.75".
· In other cases or when rigorous adjustment is required
1. Connect a resistance tube (or column) that can create pressure similar to the desired delivery pressure at 1.0mL/min or less and wait until delivery becomes stable.
2. While monitoring fluctuation on the pressure monitor of the instrument, gradually increase the set value of [COMP] from 0.45 in 0.05 increments to find the COMP value with the minimum fluctuation on the pressure monitor.