Pekcan, OnderKara, SelimArda, Ertan2024-06-122024-06-1220070927-6440https://doi.org/10.1163/156855407779230344https://hdl.handle.net/20.500.14551/19568Phase transitions of kappa-iota-carrageenan hybrid in various types of salts were studied using photon transmission technique: NaCl, KCI, MgCl2, CaCl2 and KCl+CaCl2 were chosen as the salt solutions for the carrageenan hybrid. Coil-to-helix (c-h), helix-to-dimer (h-d) and back to helix-to-coil (h-c), dimer-to-helix (d-h) phase transitions of carrageenan hybrid in these mono- and bivalent cation solutions were studied upon cooling and heating, respectively. Photon transmission intensity, It, was monitored against temperature to determine the (c-h), (h-d) and (h-c), (d-h) transition temperatures (T-ch, T-hd and T-hc, T-dh) and activation energies (Delta E-ch, Delta E-hd and Delta E-hc, Delta E-dh) of carrageenan hybrids. Two distinct transition regions were observed both during heating and cooling of the carrageenan-bivalent salt systems. During the heating process, at first dimers decompose into helices by making a (d-h) transition. Then at the high temperature region, a (h-c) transition takes place. During cooling, back transitions repeat themselves. However, the carrageenan-monovalent salt system presented only (c-h) and (h-c) transitions during the cooling and heating processes, respectively. A hysteresis was observed between (h-c)-(c-h) and (d-h)-(h-d) transitions for the monovalent and bivalent cation systems respectively.en10.1163/156855407779230344info:eu-repo/semantics/closedAccessCarrageenan HybridActivation EnergyHysteresisTransition TemperaturePhase TransitionSalt SolutionConformational TransitionSol-GelIndicative EvidenceLiquid-CrystalReal-TimeGelationSystemsDynamicsReleaseArticle141119Q2WOS:0002443399000012-s2.0-33847141777Q2