1. Evidence for singlet-oxygen generation and biocidal activity in photoresponsive metallic nitride fullerene-polymer adhesive films.
- Author
-
McCluskey DM, Smith TN, Madasu PK, Coumbe CE, Mackey MA, Fulmer PA, Wynne JH, Stevenson S, and Phillips JP
- Subjects
- Cell Survival drug effects, Escherichia coli cytology, Fullerenes pharmacology, Materials Testing, Membranes, Artificial, Metals chemistry, Nitrogen chemistry, Nitrogen pharmacology, Photochemistry methods, Polymers chemistry, Staphylococcus aureus cytology, Disinfectants chemistry, Disinfectants pharmacology, Escherichia coli drug effects, Fullerenes chemistry, Metals pharmacology, Singlet Oxygen chemistry, Staphylococcus aureus drug effects
- Abstract
The adhesive properties, as measured by bulk tack analysis, are found to decrease in blends of isomerically pure Sc3N@I(h)-C80 metallic nitride fullerene (MNF) and polystyrene-block-polyisoprene-block-polystyrene (SIS) copolymer pressure-sensitive adhesive under white light irradiation in air. The reduction of tack is attributed to the in situ generation of 1O2 and subsequent photooxidative cross-linking of the adhesive film. Comparisons are drawn to classical fullerenes C60 and C70 for this process. This work represents the first demonstration of 1O2 generating ability in the general class of MNFs (M3N@C80). Additional support is provided for the sensitizing ability of Sc3N@I(h)-C80 through the successful photooxygenation of 2-methyl-2-butene to its allylic hydroperoxides in benzene-d(6) under irradiation at 420 nm, a process that occurs at a rate comparable to that of C(60). Photooxygenation of 2-methyl-2-butene is found to be influenced by the fullerene sensitizer concentration and O2 flow rate. Molar extinction coefficients are reported for Sc3N@I(h)-C80 at 420 and 536 nm. Evaluation of the potential antimicrobial activity of films prepared in this study stemming from the in situ generation of 1O2 led to an observed 1 log kill for select Gram-positive and Gram-negative bacteria.
- Published
- 2009
- Full Text
- View/download PDF