The peptide Amyloid-ß (Aß is the main constituent of senile plaques and is a pathological hallmark in Alzheimers disease. Recently, we have investigated how the fragment Aß(25-35) and Aß(22-40) influence the dynamics in phospholipid membranes [1,2]. Most important, we could demonstrate, that the insertion of Aß fragments into DMPC/DMPS membranes increases the lateral diffusion velocity, especially in the liquid-crystalline phase. This phase is the biologically most relevant one. The published results where obtained on the time-of-flight spectrometer NEAT with an energy-resolution 93 µeV. Here, we like to confirm and extend these results with a better energy-resolution of approx. 1 and 15 µeV.