Invited by Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences (TIPCCAS), Dr. Hongwei Duan from School of Chemical and Biomedical Engineering, Nanyang Technological University visited TIPC on Sep, 7 and gave an academic report entitled Amphiphilic Nanocrystals: Self-Assembly and Applications in Nanomedicine.

In the report, Dr. Hongwei Duan introduced the self-assembly of amphiphilic nanocrystals and its applications in nanomedicine.They have developed a new class of amphiphilic nanocrystals with mixed polymer brush coatings, which are synthesized via sequential "grafting to" (ligand exchange) and "grafting from" (surface initiated polymerization) reactions on functional nanocrystals of selective sizes and morphologies. One major finding is that the integration of gold nanocrystals (nanoparticles and nanorods) with two types of chemically distinct polymer grafts, which are analogous to block copolymers as a whole, creates a new type of hybrid building blocks inheriting the plasmonic properties of the nanocrystals and amphiphilicity-driven self-assembly of block copolymers to form well-define ensembles such as vesicles and closely-packed 2D arrays at oil-water interfaces. Of particular interest for biomedical applications is that the disruption of the plasmonic vesicles can be triggered by stimuli mechanisms inherent to either of the polymer or the nanocrystal. The plasmonic vesicles were further used to target cancer cells and monitor the drug release in real-time. Recent advances in nanocrystal synthesis and controlled surface-initiated polymerization have opened a wealth of possibilities to expand this concept to other types of nanocrystals and to integrate different types of nanocrystals into multi-functional vesicles. The development of multi-functional vesicles containing stimuli-responsive polymers could enable their broader applications in biosensing, multi-modality imaging and theranostic nanomedicine. They have also demonstrated that the interfacial assembly of amphiphilic nanocrystals can be loaded on graphene paper, leading to a new class of flexible biosensors.