Liposomes are small spherical particles of lipid bilayer(s) self-assembled in water. Ever since their discovery in the 1960s, liposomes have proved to be an enabling tool in fundamental research (e.g., cell biology, biophysics and biotechnology) and invaluable material in industry (e.g., food, drug delivery and cosmetics). With the support from the Macromolecular, Supramolecular and Nanochemistry Program of the NSF Chemistry Division, Professor Zhan of Auburn University is developing a new type of liposomes - Janus liposomes. Unlike conventional (symmetrical) liposomes, Janus liposomes contain two opposing halves with different chemical identity and surface characteristics. Professor Zhan's research focuses on harnessing the unique properties of Janus liposomes to create new lipid materials with advanced functionality. Professor Zhan is also creating new opportunities for high school students and underrepresented college students in the region to participate in research on lipid materials and self-assembly chemistry. Professor Zhan's work aims to make discoveries with significant scientific and industrial impact and to help nurture next-generation workers who have advanced skills in a key branch of chemistry.
Janus liposomes display heterogeneous surface chemistry and broken symmetry, properties distinct from those of conventional liposomes. These unique attributes fundamentally alter the ways Janus liposomes interact with each other and with the surrounding media, which have yet to be explored and understood. To this end, Professor Zhan studies the preparation, self-assembly and motional behavior of Janus liposomes. In the first direction, Professor Zhan is developing a general method to prepare Janus liposomes in batch quantity. This new method helps to remove a bottleneck hampering the advancement of a promising new area and can enable other interested researchers to make contributions to this field. In addition, he is also using Janus liposomes to build complex lipid architectures via self-assembly and to achieve their controlled motion through selective functionalization of specific lipid domains. These activities begin to provide a detailed understanding on the self-assembly of Janus liposomes and establish several robust methods to drive, direct and control motion of aqueous-suspended Janus liposomes.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.