BIOLOGICAL ACTIVITIES OF PHTHALOCYANINES–VII. PHOTOINACTIVATION OF V-79 CHINESE HAMSTER CELLS BY SELECTIVELY SULFONATED GALLIUM PHTHALOCYANINES

Abstract Gallium chloride phthalocyanines sulfonated to different degrees were tested for their ability to inactivate V-79 Chinese hamster cells in the presence of red light. The mono- and disulfonated compounds were the most active whereas the tri- and tetrasulfonated complexes were completely void of photoactivity. In addition, large variations in photoactivity were observed among the four isomeric disulfonated derivatives with the most hydrophobic isomer exhibiting the highest photoactivity. Prolonged exposure to the disulfonated complex resulted in increased photosensitization. Complexing the dye with Al instead of Ga resulted in a slightly increased photosensitizing effect.     

Phthalocyanine-peptide conjugates via palladium-catalyzed cross-coupling reactions

Phthalocyanines (Pc) were conjugated with peptide moieties to improve their target selectivity for potential use as fluorescence and/or positron emission tomography (PET) probes in medical imaging. Three synthetic methods based on palladium-catalyzed cross-coupling reactions (Sonogashira, Buchwald-Hartwig, and Suzuki-Miyaura) were investigated. Using these methods, a series of peptides monofunctionalized with Pc at the N/C-terminal position or on a phenylalanine side chain was obtained in good yields and characterized.     

Partially miscible polystyrene/polymethylphenylsiloxane blends for nanocomposites

The potential of polystyrene/polymethylphenylsiloxane (PS/PMPS) blends as a matrix for nanocomposites is investigated. It was proven by dynamic rheometry and conductivity measurements that PMPS effectively disperses carbon nanotubes, as was already known for polydimethylsiloxane (PDMS). The phase behaviour of PS/PMPS blends was investigated using differential scanning calorimetry or modulated temperature differential scanning calorimetry. The blends were found to exhibit partial miscibility, in contrast to the known immiscible behaviour of PS/PDMS blends. A miscibility window exists for PS/PMPS blends containing less than approximately 10 wt% PMPS.     

Oxidation and reactivity of nitrogen- and phosphorus-doped heterofullerenes

Density functional theory (DFT) calculations suggest significantly different oxidation behaviour for phosphorus-doped heterofullerenes compared to their pure and nitrogen-doped counterparts, due to formation of a phosphene oxide. This oxide is not thermally labile, suggesting stable phosphofullerenes are likely to be C(59)POH and (C(59)PO)(2). In contrast, azafullerenes form stable epoxides when oxidised. We calculate the effect of oxidation on radical pairing and hydrogen passivation. Notably while the C(59)N radical behaves as a donor, C(59)PO will be an acceptor.