Solvent contrast variation study of DNA nanocarriers based on Transportan peptides

Cell-penetrating peptides (CPPs) are short amino acid sequences that can transport molecules or DNA into cells. Delivery of nucleic acids (DNA or RNA) into cells is attracting huge attention as a potential means to treat genetic diseases. We seek to determine the nanostructure of complexes formed between DNA and oppositely charged peptides, based on Transportans, which are a class of CPPs derived from natural sequences of wasp venom proteins and human neuropeptides. We will perform small-angle neutron scattering, using unique capabilities of the Sans2d beamline at ISIS, to investigate the structure of model CPPs in complexes with DNA using contrast variation with mixtures of deuterated and normal water. The scattering length densities of DNA or peptides within complexes will be matched in different samples, to determine the ordering of the components.