Center for Functional Nanomaterials Seminar

Part I - Histidine–rich sequence peptides were used to fabricate morphology-controlled nanocrystals on the surface, inspired by nature that various inorganic nanocrystals are produced accurately, efficiently and reproducibly in biological systems. Here biomineralization of nanotubes was developed by incorporating these sequenced peptides on the template peptide nanotubes. The biological recognitions of the specific peptide sequences toward particular metals lead to the efficient inorganic coatings such as, Ag, Pt, Cu on the nanotubes. This method allowed us to produce nanotubes uniformly coated by highly crystalline metal nanocrystals with the high-density coverage. It’s demonstrated that the size, shape and packing density of the nanocrystals can be regulated by changing the pH of the reaction solution which caused the conformation change of the sequence peptides. By this means, different inorganic nanowires can be synthesized with tunable surface morphology and this will result in tunable physical properties that could be used as the building blocks for the fabrications of nanodevices and nanosensor.
Part II - Synthesis of next generation magnetic nanoparticles (MNP) preparations through the use of systematic evaluations of polymer libraries and optimized conjugation chemistries was explored. There are more than 30 new polymers had been screened and 6 of them were selected for the detailed investigation. It’s found that modified dextran and starch coated iron oxide nanoparticles have ultra high relaxivity(keys for the sensitivity of MRI imaging) and stability with relative small size. Also, the size of the MNP could be tuned from 25 to 100 nm by changing the experimental conditions. Meanwhile, the cell uptake of these nanoparticles was studied and results showed the modification of the coated polymers can dramatically increase the cell uptake of nanoparticles.