Supramolecular Chemistry; Molecular Recognition and Self-Assembly; Optical Probes for Biological Imaging.
The main theme of our research is molecular recognition. We would like to understand how molecules recognize and interact with each other, to exploit molecular interactions in the self-assembly of complex structures, and to create functional materials from molecular assembly and recognition.
1. Self-assembly of interlocked structures
Catenanes are topologically non-trivial molecules with two or more mechanically interlocked rings. The constituting rings of a catenane are linked together due to the 3D spatial arrangement but not the atom connectivity of the respective rings, and are not separable unless one ring is broken. Because of this non-trivial topological structure, catenanes and related interlocked molecules have long been a synthetic curiosity and challenge. The unique mechanical properties of the interlocked rings also make catenane a promising candidate as basic units of molecular switches, sensors, electronics, memory, actuators, and many more other novel functional materials.
In this project, we would like to exploit different strategies to assemble simple building blocks into high-order interlocked structures, so as to push the limit of structural complexity in molecular self-assembly. The work will involve organic/inorganic synthesis and a range of characterization methods such as 1D and 2D NMR, mass spectrometry and UV-Vis spectroscopy.
2. Chemical probes for biological imaging
Optical imaging, with analyte-responsive fluorescent probes in particular, is a widespread technique in chemical biology for the study of biomolecules and metal ions in different biochemical events, providing a facile and convenient way to elucidate their roles in cell physiology. As the cell is a dynamic mixture of water, ions, small molecules and macromolecules that are continuously interacting, extracting information about a specific molecule from this complex mixture, without interfering and interference from the environment, requires chemical probes that are reactive to sensitively and selectively report the presence of the molecule in interest while inert towards all other cellular components.
In this project, we will employ our knowledge in molecular recognition to develop new fluorescent probes that can selectively detect the presence of small organic molecules of biological interest, and to use these probes to monitor the changes in level of these biomolecules in biological samples such as live cells and small animals under different physiological conditions. The work will involve synthesis, characterization of the optical properties and cellular imaging with the synthesized probes.