CYCLIC VOLTAMMETRIC STUDY OF REDOX-ACTIVE SURFACTANT BY HYDROGEL-MODIFIED ELECTRODE

The dissolved states of redox-active non-ionic surfactant (FPEG) in th e swollen state of N-isopropyl acrylamide (NIPA) hydrogel have been st udied by using a gel-modified electrode. The pronounced decrease in th e peak current and the negative shift in the formal potential of CV at the gel-modified electrode, as compared with the normal GC electrode, was observed in the micelle-solution; this indicates that the diffusi ve FPEG molecules which form the micelle hardly penetrate into the NIP A gel. This result suggests that there exists all interaction between FPEG molecules and the NIFA gel in the vicinity of the surface of the NIPA gel in the micelle-solution. However, this also indicates that a small amount of FPEG molecules which can form micelles exist in the NI PA gel. (C) 1997 Elsevier Science Ltd.