Abstract:
Poly(methylamido amine) (PMAAM), poly(methylamide) (PMA), and poly(methylamido methyl amine) (PMAMAM) are spectroscopically analogous to poly(amido amine) (PAMAM) dendrimers, and were used to monitor and influence photo-driven processes. By varying the incorporated functionalities, metal ion uptake and the observed ground and excited electronic states change. Functional groups play a vital role in the solution phase, UV-induced nanoparticles synthesis. Quenching studies show that multiple site contributions yield the observed metal ion uptake. Dendrimer and oligomeric scaffolds provide a highly ordered environment to facilitate photo-induced processes; however, current electron transfer mechanisms cannot be elucidated in this work. The initial metal ion uptake contributes drastically to the excited state processes and the synthesized nanoparticle. pH influences the bound precursors altering the morphology of the produced nanoparticle after irradiation. Scaffold-mediated nanoparticles exhibit sizes on the order of the scaffold diameter which varies as a function of generation. The physical properties, such as magnetism, greatly change from the observable bulk properties below 10 nm. Coating these particles in silica such that the final composite size approaches 100 nm enables magneto-optical solution application, but directly attaching silica to the magnetic nanoparticle surface proves difficult. Magnetic nanoparticle surface modification aids in attaching these particles to the surface of silica.
