Structure of Polyampholyte Gels and Their Behavior with Respect to Applied External DC Electric Field

Electroosmotically enhanced mass transfer through polyacrylamide gels

“…The pH was constant during the first 30 min before the field was applied, but the pH in each compartment rapidly adjusted after the field application commenced at 30 min. This is to be expected, and similar effects have been noted with poly(ampholyte) gels and in microfluidic channels [32,33]. The pH gradients measured here were similar for particle-free and particle-laden gels.…”

Stimuli‐sensitive behaviour of novel betaine‐type polyampholytes

“…Earlier the formation of a pH‐gradient inside the amphoteric network under the action of a DC electric field had been observed for amphoteric gels based on vinyl‐2‐aminoethyl ether and sodium acrylate 22. Figure 14 shows the change of pH inside a polyabetaine gel as a function of time.…”

“…The phase (or volume) transition of amphoteric macromolecules in response to their environment considerably expands our knowledge on universality of both synthetic and natural polymers. The coexistence of macroscopic multiphases in response to pH14 (re‐entrant swelling), temperature15 and DC electric field16 (‘bottleneck’ shape in both cases) as well as the existence of microsegregation,17 due to static or dynamic inhomogeneity,18 macroscopic oscillation of gel19, 20 and interpolyelectrolyte membranes,21 pH‐oscillation,22 and pH‐gradient22 under the applied DC electric field owing to combination of ‘antipolyelectrolyte’ and polarization effects, water electrolysis can be of help to model rhythmical phenomena similar to heart beat,23 and to design artificial muscles, chemo‐mechanical10 and biochemo‐mechanical24 systems, to construct actuators, environment‐sensitive semipermeable membranes, microcapsules, semiconductors, electronic devices, etc. Stimuli‐sensitive properties of polyampholytes mostly were studied with respect to annealed and quenched ones.…”

Natural and Synthetic Polyampholytes, 2

“…These results are in good agreement with the theoretical and experimental data reported by Shiga et al [91][92][93] Figure 5 represents the deswelling and oscillation of a polyampholyte gel determined by applying an electric field parallel to the long axis of a gel rod. [94] The development of a pH gradient inside a gel sample under an externally applied DC electric field was evidenced for amphoteric gels [95,96] (Figure 6). Without the applied field, the pH profile along the section of the sample is uniform and equal to 7.4.…”