Development of polymer-membrane based electrodes for suramin

Quantitative determination of fucoidan using polyion-sensitive membrane electrodes

“…As reported by Fu et al for linear polyions [50], increasing the plasticizer content of the polymer membrane to 66 wt.% DOS, 32.5 wt.% PVC, 1.5 wt.% TDMA shifted the dynamic range of the sensors to higher fucoidan concentrations. While all sensors used in the these studies were discarded after a single use, sensors can be regenerated by soaking in 3M NaCl for reuse with a minimal decrease in sensitivity, as has also been demonstrated for other polyanions [39,42]. A more promising approach would be to use a fully reversible, pulsed chronopotentiometric polymer membrane electrode, similar to that first described for the linear polycation protamine [51,52], and later developed for linear polyanions, such as heparin and pentosan polysulfate [53,54].…”

“…Therefore, ISEs used in a traditional manner (where equilibrium is established between the sensor membrane and the sample solution) are not effective for monitoring concentration changes of highly charged molecules, such as fucoidan. However, since the mid-1990s polymer membrane-based potentiometric ISEs doped with tridodecylmethylammonium (TDMA) have been used to quantitatively measure linear macromolecular polyanions, including heparin [38,39], pentosan polysulfate [40], carrageenan [41], surmarin [42], and DNA [43]. Sensors for detecting the positively charged polypeptide, protamine, and polycationic dendrimers have also been prepared by doping sensor membranes with cation-exchanger dinonylnaphthalene sulfonate (DNNS) [44,45].…”