title: Influence of structural features of carrageenan on the formation of polyelectrolyte complexes with chitosan.
abstract: The polyelectrolyte complexes (PEC) of carrageenans (CG)-κ-, κ/β-, λ-and x-CG with chitosan were obtained. The formation of PEC was detected by Fourier-transform infrared (FTIR) spectroscopy and by centrifugation in a Percoll gradient. The influence of the structural peculiarities of CG on its interaction with chitosan was studied. The results of centrifugation showed that x-CG with a high degree of sulphation (SD) was completely bound to chitosan, unlike low SD κ-CG and κ/β-CG. Binding constant values showed there was a high affinity of CG for chitosan. CG with flexible macromolecule conformation and high SD exhibited the greatest binding affinity for chitosan. The full-atomic 3D-structures of the PEC κ-CG: chitosan in solution have been obtained by the experiments in silico for the first time. The amino groups of chitosan make the largest contribution to the energy of the complex formation by means of hydrogen and ionic bonds. The most probable complexes have stoichiometries of 1:1 and 1:1.5.
authors.affiliation: G.B Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of Russian Academy of Sciences, Prospect 100 let Vladivostoku 159, Vladivostok 690022, Russia. Electronic address: morskaia@list.ru.
authors.forename: A V
authors.initials: AV
authors.lastname: Volod'ko
authors.affiliation: G.B Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of Russian Academy of Sciences, Prospect 100 let Vladivostoku 159, Vladivostok 690022, Russia.
authors.forename: V N
authors.initials: VN
authors.lastname: Davydova
authors.affiliation: G.B Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of Russian Academy of Sciences, Prospect 100 let Vladivostoku 159, Vladivostok 690022, Russia.
authors.forename: V P
authors.initials: VP
authors.lastname: Glazunov
authors.affiliation: G.B Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of Russian Academy of Sciences, Prospect 100 let Vladivostoku 159, Vladivostok 690022, Russia.
authors.forename: G N
authors.initials: GN
authors.lastname: Likhatskaya
authors.affiliation: G.B Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of Russian Academy of Sciences, Prospect 100 let Vladivostoku 159, Vladivostok 690022, Russia.
authors.forename: I M
authors.initials: IM
authors.lastname: Yermak
mesh_terms: D002351:Carrageenan / Q000737:chemistry*; D048271:Chitosan / Q000737:chemistry*; D004573:Electrolytes / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D015394:Molecular Structure; D008970:Molecular Weight; D012995:Solubility; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D004573:Electrolytes; D002351:Carrageenan; D048271:Chitosan
keywords: 3D-structure; Carrageenan; Chemical structure; Chitosan; FTIR; In silico; Polyelectrolyte complex