Chemistry and Biochemstry Department Seminar
|Category:||College Of Arts And Sciences|
|Date & Time:||
from 04:15 PM to 05:30 PM
|Sponsored by:||Chemistry & Biochemistry Deptartment|
Sweet Nanomaterials: Synthesis, Characterization and Applications
Mingdi Yan, Department of Chemistry, UMass Lowell
Glyconanomaterials, nanomaterials carrying immobilized glycans, combine the unique properties of nanometer-scale objects with their ability to present multiple copies of glycan ligands. These new materials have demonstrated potentials in biomedical imaging, therapeutics, and diagnostics. We developed a general method for coupling carbohydrates onto nanomaterials by way of the photocoupling reaction of perfluorophenyl azide. The method applies to a variety of carbohydrate structures and does not require additional chemical derivatization of the ligands. Subsequently, four analytical methods, based on fluorescence competition assay, dynamic light scattering, isothermal calorimetry, and super-microarray have been developed to determine the binding affinity (Kd) of glyconanoparticles (GNPs) with lectins. Results showed that the affinity of GNPs with lectins were several orders of magnitude higher than those of free ligands with lectins. Critical to the performance of glyconanomaterials is the proper display of glycan ligands. Comprehensive studies were conducted to investigate the impact of ligand presentation, and results showed that the binding affinity of GNPs is profoundly influenced by the coupling chemistry, the type and length of the spacer linkage, the ligand density, and the type and size of the nanoparticles. Finally, GNPs were employed to probe glycan-lectin interactions in a high-throughput fashion using lectin microarrays and glyconanoparticle arrays. Latest work on probing the interactions of GNPs and various strains of E. coli bacteria will also be presented.