We will perform SANS investigations on complexes formed between peptide amphiphiles (PAs) and the plasmid DNA pEGFP-N1. Previous SAXS data have shown that our PAs form nanoscopic fibrils or layered structures, thus potentially able to host DNA. We propose solvent matching experiments where D2O/H2O ratio will be varied to separately match the contrast of PAs and DNA. Our data will be combined with cell assays following transfection with the peptide/plasmid complexes to determine a relationship between structure and delivery.