Among other things, nanomedicine is investigating how the treatment of dangerous diseases can be made more effective and safer, as conventional therapies are often associated with considerable side effects. It is therefore of great interest to formulate drug carrier systems that can deliver active substances into cells and release them there again without exerting a cytotoxic influence on surrounding healthy cells.

This dissertation investigates the development and characterisation of nucleobase-based peptides for thermoresponsive drug release. The focus is on the synthesis, self-organisation and functionality of peptides that are able to efficiently condense and transport nucleic acids. The targeted modification of peptides with nucleobases such as thymine, cytosine and guanine creates novel nanostructures that interact with RNA through electrostatic and nucleobase interactions.

The work comprises the synthesis of different cationic peptides by solid phase peptide synthesis (SPPS) and their subsequent functionalisation with polyethylene glycol (PEG) to improve stability and biocompatibility. Nanoparticle formation will be characterised by dynamic light scattering (DLS) and transmission electron microscopy (TEM), investigating the effects of PEG length and nucleobase number on particle size and polydispersity index.

In addition, the thermoresponsive properties of the developed systems will be investigated in order to enable the controlled release of active substances. The efficiency of RNA transfection will be tested using EGFP-RNA, with results indicating the importance of nucleobase interactions and electrostatic interactions. In addition, the transporter system was analysed for cytotoxicity and transfection efficiency in different cell lines.

This dissertation thus contributes to the development of innovative biomaterials for targeted drug delivery and offers promising approaches for future therapeutic applications in gene therapy and cancer research.