|Title||Polyelectrolyte Conformation Controlled by a Trivalent-Rich Ion Jacket.|
|Publication Type||Journal Article|
|Year of Publication||2019|
|Authors||Innes-Gold, Sarah N., Philip A. Pincus, Mark J. Stevens, and Omar A. Saleh|
|Journal||Phys Rev Lett|
|Date Published||2019 Nov 01|
The configuration of charged polymers is heavily dependent on interactions with surrounding salt ions, typically manifesting as a sensitivity to the bulk ionic strength. Here, we use single-molecule mechanical measurements to show that a charged polysaccharide, hyaluronic acid, shows a surprising regime of insensitivity to ionic strength in the presence of trivalent ions. Using simulations and theory, we propose that this is caused by the formation of a "jacket" of ions, tightly associated with the polymer, whose charge (and thus effect on configuration) is robust against changes in solution composition.
|Alternate Journal||Phys. Rev. Lett.|