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In the present study, the role played by the reactants concentration on the nonlinear response of a Belousov-Zhabotinsky (BZ) system to the addition of a self-assembling non-ionic polymer, poly(ethylene glycol) (PEG), has been assessed. The oscillatory parameters are influenced to an extent that significantly depends on the concentration of both the polymer and the Belousov-Zhabotinsky components. The effects obtained were attributed to the reaction among some of the BZ key species and the backbone and the alcoholic functional groups of the polymer, both in its monomeric and aggregated forms.Support to the proposed perturbation mechanism has been provided by performing numerical simulations with the MBM model and by characterizing the physicochemical behavior of the PEG aqueous solution by means of viscosimetric and spectrofluorimetric measurements.

The transition from planar fronts, trigger waves or solitary pulses to spirals in excitable media, has\ud attracted increasing interest in the past few decades, mainly because of its relevance for biological and\ud medical applications. In this paper we describe a new and convenient method for spiral generation\ud starting from symmetric wavefronts. By using the micelle-forming zwitterionic surfactant N-tetradecyl-\ud N,N-dimethylamine oxide in a Belousov–Zhabotinsky solution, it is possible to control to a large extent\ud the domains where spirals can be spontaneously generated. The mechanism responsible for the\ud wavefront break up lies in the interaction of the propagating waves with the unexcitable regions formed\ud by the interaction of the surfactant with some of the Belousov–Zhabotinsky key intermediates