Synthesis and Investigation of New Core-Shell Nanoparticles as Molecular Carrier Systems

• Antragsteller: Professor Dr. Rainer Haag
• Fachliche Zuordnung: Präparative und Physikalische Chemie von Polymeren
• Förderung: Förderung von 2008 bis 2012
• Projektkennung: Deutsche Forschungsgemeinschaft (DFG) - Projektnummer 49558485

The objective of this joint proposal is to develop highly efficient syntheses for new dendritic coreshell nanocarriers and to systematically investigate the effects of molecular architecture on their encapsulation and transport of hydrophobic molecules in aqueous systems. By combining the expertise of the Guan group (UC Irvine, USA) for one-pot synthesis of hydrophobic polyolefin cores with controllable topologies and the Haag group (Freie Universitaet Berlin, Germany) for efficient synthesis of hydrophilic and biocompatible polyglycerol shells, the proposed study is aimed to develop efficient methodology for the synthesis of core-shell nanocarriers and to reveal basic structure-property information on the resulting new amphphilic molecular architectures. In the proposed joint studies, first, the Guan group will synthesize a series of hydrophobic polyolefin cores with architectures ranging from linear, hyperbranched, to dendritic by using their chain walking polymerization methodology developed with their prior NSF CAREER grant. Using a chain walking catalyst, dendritic nanoparticles including core-shell nanostructures have been obtained in one-pot polymerization. The synthetic efficiency, versatility, combined with the unique structure and properties for the polymers make this strategy exciting for further investigation. These cores will carry different functional groups such as aromatic units in the interior and primary hydroxyl or alkyne groups on the surface. Subsequently, the Haag group will graft biocompatible and hydrophilic dendritic polyglycerol shells from/to the hydrophic polyolefin cores by using their established methodologies. Finally, the encapsulation and molecular transport properties of the synthesized core-shell nanocarriers for representative hydrophobic molecules in aqueous solution will be investigated by UV/Vis and fluorescence spectroscopy. The basic solution properties of these core-shell nanocarriers and their aggregation behavior will also be carefully examined by light scattering and cryo- TEM. The understanding of structure-property relationships gained from this study will provide critical insight for designing highly efficient molecular nanocarriers that may find potential applications for ink formulation and drug delivery. The intellectual merit of this proposed activity is 2-fold: (1) the true marriage between two unique and complementary new synthetic methodologies shall lead to the development of highly efficient synthetic routes for accessing novel core-shell nanocarriers; (2) through systematically varying the architecture/structure of the core-shell constructs and investigating their solution and molecular transport properties, important insights will be gained on how to design efficient molecular nanocarriers for a broad range of applications. The broad impacts of this joint study is numerous and significant: (1) Impact to the industry: successful development of facile synthesis of efficient molecular nanocarriers shall have enormous impacts on various industries including health care, drug formulation and delivery, ink and paint formulations. (2) Impact to nanoscience: efficient methods for making biocompatible, complex and multifunctional soft nanomaterials shall accelerate many nanotechnology developments including nanomedicine and medical diagnostics. (3) Educational impacts: The proposed multi-disciplinary and international collaborative research activity will provide excellent training for students in many areas including organic synthesis, organometallic, polymer synthesis and physical property studies, and nanoscience. This will provide great opportunities to train graduate and undergraduate students, especially for minority and women students. The frequent exchanges between the two groups will not only expose the students to different expertise and techniques, but provides them opportunities to gain international experience in scientific collaborations.

• DFG-Verfahren: Sachbeihilfen
• Internationaler Bezug: USA
• Beteiligte Person: Professor Zhibin Guan, Ph.D.