​​​Lukaš Ustrnul​

Development of adaptable supramolecular chirality sensors is important for the industry and academia. Chiral molecules, in nform of enantiomers, are commonly used in the pharmaceutical, food, perfume, cosmetic, and agricultural industries. In biological ecosystems, chiral molecules are metabolized, absorbed, and excreted selectively, and their biological effects can vary significantly. Therefore, the environmental impact of different stereoisomers can be radically different. Standard analysis methods that do not distinguish the chirality of molecules may underestimate the effects of these compounds. In this project, we designed and synthesized new receptor molecules through both supramolecular interactions and covalent bonding. By investigating the structure, optical, and supramolecular properties of the obtained receptor molecules, we reached several new compounds with the potential to be applied for separation, isolation, and detection of bioactive compounds and environmental pollutants. We developed environmentally friendly mechanosynthesis methods to reduce waste production during the synthesis process of organic compounds. Additionally, we studied formation of oligomeric macrocyclic receptors and developed methods for obtaining both mono- and multifunctional macrocyclic compounds. We initiated research on the creation of supramolecular materials and demonstrated that materials for enantioselective electronic noses can be easily prepared using porphyrins and chiral hemicucurbiturils. We also investigated the correlation between the circulardichroism signal generation and molecular orbitals and geometries modelled by quantum chemical methods. We also showed that the signal of the studied optically active sensor molecules can be amplified via interaction with inorganic chiral materials. The results of the project were published in number of research articles and two patents were applied for.

Chiral pollution is an environmental topic of crucial importance, considering that a large number of chemicals spreading into the environment, for example pesticides, are chiral substances. However, usually the stereoisomerism of contaminants is not considered, although the biological activity of enantiomers is significantly different, making their recognition critical for environmental control. Enantiomeric excess is currently determined by off-site analysis, requiring collection, transportation, eventual pre-treating of the sample, and expensive instrumentations and specifically trained staff. Thus, providing devices able to allow for rapid on site detection and chiral discrimination of target analytes would have a dramatic impact in all the fields of environmental control with significant economic benefits. The development of chemical sensors has been conceived to bypass restrictions related to classical analytical protocols and supports the use of conventional laboratory techniques for environmental control. While the technological foundation for chemical sensors already exists, it has been difficult to apply them to chiral discrimination and analysis, due to the lack of suitable solid state receptors. The main aims of the project are: a) the development of novel molecular receptors, mainly based on porphyrin derivatives, b) integration of the receptors with different nanostructures and characterization of their solid state organization, c) deposition of the structures onto transducer surfaces, d) testing and validation of the new chemical sensor devices with enantiomeric pairs of model analytes. The synergistic complementary know-how of six academic units and two private companies will allow a breakthrough development through delivery of sensing probes ranging from the synthesis of macrocyclic molecular receptors to the building and testing of analytical and electronic parts for final, field-capable devices.