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Development of New Dendrimer-based Drug Encapsulation Polymeric Materials

Stephanie Fox and Asare Nkansah,Ph.D.
Dept. of Chemistry and Physics
Chicago State University, Chicago, Il 60628

ABSTRACT

This paper describes a new approach to loading cisplatin onto dendrimer drug carrier. Hydroxy-functionalized dendrimer (Boltorn H20 and H30) was converted to acetoacetoxy (AcAc) functionality by transesterification reaction. Cisplatin, an anticancer drug, was loaded onto the dendrimer using enamine chemistry.  Enamine formation and chemical stability of cisplatin after encapsulation into the dendrimers was confirmed by FTIR and UV. X-ray diffractometer (XRD) studies were made on drug-loaded dendrimers to investigate the crystalline nature of drug after encapsulation. Scanning electron microscope confirmed smooth a relatively smooth surface morphology. Drug release studies were performed at low pH (gastric fluid environment), neutral pH (intestinal fluid environment). The release rate was monitored in order to estimate transport parameters. Swelling studies were performed in simulated fluid environment.

Computational Investigation of the Electronic Structure of Cobaloxime Compounds: Determining the Role of Structure on Hydrogen Photocatalytic Ability

Gilbert N. Mbahand Kristy L. Mardis, Ph.D.
Dept. of Chemistry and Physics
Chicago State University, Chicago, IL

ABSTRACT

Global warming and the world's high demand for energy are driving scientists to look for alternative ways to produce clean energy. Supramolecular cobaloxime compounds have been suggested as promising photocatalytic converters of solar energy to hydrogen fuel using water as the raw material. However, many of the current cobaloxime compounds have slow rates of electron transfer. This research computationally investigates the relationship between the electronic distribution of photocatalysts and their structures using density functional theory (DFT) and time dependent density functional theory (TDDFT). Results for Co (dmgBF2)2pyridyl-PDI complex showed that the electron density in the highest occupied molecular orbital was localized on the photosensitizer portion of the complex, indicating that the electrons may not be able to flow to the catalytic portion. Similar calculations show less localization of electron density for the Co (dmgBF2)2pyridyl-Ru(bpy)2(L-pyr)) photocatalyst. Since this catalyst also has a higher rate of electron transfer, these orbital results may partially explain the poor efficiencies observed experimentally. Modified photocatalysts with non-pyridyl linkages may lead to improved efficiencies.