On the pH-responsive, charge-selective, polymer-brush-mediated transport probed by traditional and scanning fluorescence correlation spectroscopy.

ABSTRACT: The complete and reversible charge-selective sequestration of fluorophores by a weak polyelectrolyte brush, poly(2-(dimethylamino)ethylmethacrylate) (PDMAEMA) was demonstrated using fluorescence correlation spectroscopy (FCS). The chemistry and thickness of the weak polyelectrolyte PDMAEMA was tuned reversibly between neutral and cationic polymer forms. Thus, by switching the pH successively, the brush architecture was tuned to selectively trap and release anionic dye probes while continuously excluding cationic molecules. In addition, line-scan FCS was implemented and applied for the first time to a synthetic polymer system and used to identify a new, slower diffusion time on the order of seconds for the sequestered anionic probe under acidic conditions. These results, which quantify the

SUBMITTER: Daniels CR 

PROVIDER: S-EPMC3671586 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature