Leu-enkephalin self-aggregation analyzed by liquid chromatography and mass spectrometry

- The possible aggregation of leucine-enkephalin has been evaluated.
- Liquid chromatography was employed for liquid phase, mass spectrometry for gas phase.
- Aggregation figures detected by the two techniques were different.
- Aggregates were found to be environment-dependent.
- Some of the species formed in liquid phase were apparently retained in gas phase.