Mohamed Nilam

• The goal of my Ph.D. thesis is the development of supramolecular sensing ensembles based on host-guest complexes for the detection of biological molecules and for monitoring membrane translocation as well as enzymatic transformation. Moreover, these host-guest complexes can be utilized to characterize mixed ligand gold nanoparticles and the deaggregation of perylene-based dyes. The first part of the thesis focuses on the development of novel, robust, simple, and economic fluorescence-based ODC enzyme assay. The second part of the thesis introduces a fluorescence-based biomembrane assay for molecular recognition by the macrocyclic host inside the liposome. In general, supramolecular receptor molecules suffer from low affinity to analytes; therefore, we have introduced a liposome-based sensing approach based on the supramolecular tandem membrane assay principle. The liposome-encapsulated receptor molecules provide higher sensitivity than a homogeneous solution. The third part of the thesis focuses on the determination of membrane permeability and activation energy. Time-resolved monitoring of membrane translocation of analytes is of utmost importance in membrane research. We have introduced a fluorescent artificial receptor membrane assay (FARMA), which is used to monitor in real-time the permeation of indole derivatives through liposomal membrane. FARMA method is a label-free method that enabled the determination of permeation rate, permeability coefficients, and activation energies. The fourth part of the thesis focuses on the characterization of mixed ligand gold nanoparticles and the sensing of the lysine decarboxylase product. In the last part, we report that host-guest complexation affects aggregation of perylene diimide (PDI) dyes, wherein complexation of PDIs by CB7 and CB8 enhances the fluorescence and reduces the self-aggregation of the PDI in aqueous solution.