Small peaks compared to literature
Experimental settings are copied from literature data but peaks are (much) smaller than expected.
- Differences in detection parameters. Applying the same ECD potential does not guarantee the same effective cell potential if another reference electrode is used.
- The working electrode area may differ: a larger area gives more signal (but also more noise).
- A difference in cell geometry can give a different outcome.
- Differences in chromatographic settings. For example, the pH of the mobile phase usually has a major effect on peak height.
Method settings from literature may need further optimization. Always check the signal-to-noise ratio when using a bit different potential settings (test a few larger and smaller in 0.1 V steps).
Adapt the working potential in case the reference electrode is not the same type. A Pd type ref usually has a larger potential by itself, compared to a AgCl salt bridge ref. For example, under acidic mobile phase conditions the applied potential in the ECD of 800 mV vs Ag/AgCl is the same as applying 560 mV vs HyREF.