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Synthetic amphiphilic polymers have been established as potentially efficient agents to combat widespread deadly infections involving antibiotic resistant superbugs. Incorporation of poly(ethylene glycol) (PEG) side chains into amphiphilic copolymers can reduce their hemolytic activity while maintaining high antibacterial activity. Our study found that the incorporation of PEG has substantially different effects on the hemolytic and antibacterial activities of copolymers depending on structural variations in the positions of cationic centers relative to hydrophobic groups. The PEG side chains dramatically reduced the hemolytic activities in copolymers with hydrophobic hexyl and cationic groups on the same repeating unit. However, in case of terpolymers with cationic and lipophilic groups placed on separate repeating units, the presence of PEG has significantly lower effect on hemolytic activities of these copolymers. PEGylated terpolymers displayed substantially lower activity against Staphylococcus aureus (S. aureus) than Escherichia coli (E. coli) suggesting the deterring effect of S. aureus’ peptidoglycan cell wall against the penetration of PEGylated polymers. Time-kill studies confirmed the bactericidal activity of these copolymers and a 5 log reduction in E. coli colony forming units was observed within 2 h of polymer treatment.

We have found that poly (4-vinylpyridine) (P 4 VP) and poly (methylmethacrylate) thin films can be etched with ultraviolet A (UVA) radiation. Furthermore, we also found that dermal fibroblasts could be cultured successfully on the P 4 VP polymer, with a doubling time comparable to tissue culture Petri dish standards. Consequently, we were able to grow tissue on P 4 VP substrates, this could easily be lifted using UVA radiation. The cell sheets that were removed were then re-plated at a lower density and a series of assays was performed at 3 and 6 days. Although only a small amount of damage was discernable at day 3 nearly complete recovery was observed at day 6. The technique was used to pattern areas within the tissue, where other types of cells could be inserted. To demonstrate the technique, a hybrid tissue layer was produced, in which the dermal fibroblasts in a circular area at the center of the sample were removed by exposure through a mask. A keratinocyte layer was inserted, which adhere to the fibroblast layer forming a tissue with integrated layers of two distinct cell types. This article describes a new polymer, which is photosensitive and can be used for cell culture. Consequently, the tissue cultured on this polymer can be etched through a mask using ultraviolet A to produce patterned regions with different types of cells.