Systemic chemotherapy remains the backbone of many cancer treatments. Due to its untargeted nature and the severe side effects it can cause, numerous nanomedicine approaches have been developed to overcome these issues. However, targeted delivery of therapeutics remains challenging. Engineering microrobots is increasingly receiving attention in this regard. Their functionalities, particularly their motility, allow microrobots to penetrate tissues and reach cancers more efficiently. Here, we highlight how different microrobots, ranging from tailor-made motile bacteria and tiny bubble-propelled microengines to hybrid spermbots, can be engineered to integrate sophisticated features optimised for precision-targeting of a wide range of cancers. Towards this, we highlight the importance of integrating clinicians, the public and cancer patients early on in the development of these novel technologies.

In dieser Arbeit werden Strategien zur Entwicklung von biohybriden Photoelektroden, die Licht in elektrische Energie umwandeln, demonstriert und diskutiert. Der natürliche Photonen-transformierende Superkomplex der oxygenen Photosynthese aus Thermosynechococcus elongatus, das Photosystem I (PSI), kann durch die nicht-native Interaktion zum Redoxprotein Cytochrom c (Cyt c), erfolgreich funktional in Elektroden integriert werden. Hierfür wurden unterschiedliche Strategien entwickelt, z. B. bilden beide Biokomponenten unspezifische Komplexe in Lösung und assemblieren gemeinsam auf modifizierten Goldoberflächen. Aus der Kontaktierung des PSI mit einer thiol-modifizierten Goldelektrode via Cyt c ergeben sich unidirektionale kathodische Photoströme. DNA, als ein Polyelektrolytmatrixelement, kann zum Aufbau von 3D-Protein-Mehrschichtarchitekturen höherer Stabilität und Leistungsfähigkeit verwendet werden. Der Einsatz von mesoporösen Indium-Zinnoxid-Elektroden vergrößert die Photostromgenerierung um mehr als eine Größenordnung, wodurch sich hieraus skalierbare transparente Photobioelektroden mit hohen Quanteneffizienzen (bis zu 30%) erzeugen lassen. / In this thesis, strategies are demonstrated and discussed for the development of biohybrid photoelectrodes transforming light into electrical energy. The natural photon-to-charge carrier converting super-complex from oxygenic photosynthesis of Thermosynechococcus elongatus, photosystem I (PSI), can be functionally implemented into such electrodes, due to the non-native interaction with the small redox protein cytochrome c (cyt c). Different strategies have been developed, e. g. both biocomponents form complexes in solution and self-assemble on modified gold-surfaces. The electrical connection of PSI to thiol-modified gold electrodes via cyt c results in unidirectional cathodic photocurrents of high efficiency. DNA, as a polyelectrolyte matrix element, can be used to build up 3D protein multilayer architectures of higher stability and performance. The use of mesoporous indium tin oxide electrodes further enhances the photocurrent generation more than one order of magnitude, thus resulting in scalable transparent photobioelectrodes of high quantum efficiencies (up to 30 %).