Detailed dissociative electron attachment studies on the amino acid proline

We present a detailed study on the fragmentation of proline (Pro, C5H9NO2) upon attachment of low energy electrons (<12 eV). Previous investigations on dissociative electron attachment to Pro are partly confirmed, extended and also in some points vitiated. A total of 11 fragment anions, with [Pro-H]− being the most abundant one, has been observed and the present results indicate that the formation of [glycil-yl]− from Pro cannot be induced by slow electrons. This work supplements existing work on amino acids and therefore improves the understanding of the interaction between electrons at sub-ionization energies and molecules of biological interest.