Stimuli-responsive rotaxanes as a novel molecular switching platform for ratiometric electrochemiluminescent sensors

• Applicant: Professor Dr. Jochen Niemeyer
• Subject Area: Organic Molecular Chemistry - Synthesis and Characterisation ; Analytical Chemistry
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 566903340

The aim of this project is to develop new chemosensors for the ratiometric detection of analytes based on electrochemiluminescence. For this purpose, switchable rotaxanes will be equipped with ECL luminophores so that the presence of the analytes leads to a stimuli-induced conformational change and thus to a change in ECL emission. This concept is based on the expertise of the two applicants in the fields of electrochemiluminescence and synthesis and application of interlocked molecules and thus represents an interdisciplinary approach to the development of new ECL chemosensors. The research program is supported by an international exchange of the participating PhD students. To develop the ECL-active rotaxanes, the group will first identify suitable combinations of ECL luminophores, quenchers and coreactants. On this basis (and based on preliminary experiments already carried out), rotaxanes with one or two ECL luminophores on the axis and quencher units on the macrocycle will be synthesized by the group and the switching behavior will be investigated. After identification of the most suitable molecular design, the rotaxanes will be equipped with stimuli-responsive protecting groups, which can be cleaved in the presence of the desired analytes and thus enable an ECL response. These new ECL chemosensors are then used for the detection of various analytes (fluoride, hydrogen peroxide, NADH and enzymes such as lipases, amidases and galactosidases). Once the analytical application of the ECL rotaxanes has been validated, they will be used to examine real samples from environmental analysis (water samples) and biological analysis (blood, serum). This project therefore covers the entire range of design, synthesis and application of new ratiometric ECL sensors based on switchable rotaxanes.

• DFG Programme: Research Grants
• International Connection: South Korea
• Partner Organisation: National Research Foundation of Korea, NRF
• Cooperation Partner: Professor Dr. Joohoon Kim