- No chromatographic peaks are observed.
- The gradient runs, but the baseline remains constant, at the same pressure.
- ACQUITY UPLC
- Alliance HPLC
Solvents A and B are of the same composition—both aqueous or both organic.
Either there is no organic to wash off the sample or all of the sample washes off at the beginning of the run.
FIX or WORKAROUND
- Remake the solvents so that A and B are not the same composition.