title: Alginate gels with a combination of calcium and chitosan oligomer mixtures as crosslinkers.
abstract: Alginates are polysaccharides that are widely used in relation to their ability to form gels. Recently we reported that alginates may also form gels with chitosan oligomers as crosslinkers (Khong, Aarstad, Skjåk-Bræk, Draget, & Vårum, 2013). The purpose of the present study was to characterize alginate gels crosslinked with calcium and chitosan oligomers. Using two different alginates of similar molecular weights but different chemical composition, i.e. guluronic acid content of 46 and 68%, we found that both alginates could form homogeneous gels with calcium and chitosan oligomers separately and without syneresis. Systematic combinations of calcium and chitosan oligomers as crosslinkers were tested, showing that up to 50% of the calcium could be substituted with chitosan oligomers without reduction in gel strength or increased syneresis for the alginate with the lowest guluronic acid content. Furthermore, the kinetics of the combined gels were different from pure calcium alginate gels.
authors.affiliation: Norwegian Biopolymer Laboratory (NOBIPOL), Department of Biotechnology, Norwegian University of Science and Technology, 7491 Trondheim, Norway.
authors.forename: Yiming
authors.initials: Y
authors.lastname: Feng
authors.affiliation: Norwegian Biopolymer Laboratory (NOBIPOL), Department of Biotechnology, Norwegian University of Science and Technology, 7491 Trondheim, Norway.
authors.forename: Georg
authors.initials: G
authors.lastname: Kopplin
authors.affiliation: Koyo Chemical Co. Ltd, Osaka, Japan.
authors.forename: Kimihiko
authors.initials: K
authors.lastname: Sato
authors.affiliation: Norwegian Biopolymer Laboratory (NOBIPOL), Department of Biotechnology, Norwegian University of Science and Technology, 7491 Trondheim, Norway.
authors.forename: Kurt I
authors.initials: KI
authors.lastname: Draget
authors.affiliation: Norwegian Biopolymer Laboratory (NOBIPOL), Department of Biotechnology, Norwegian University of Science and Technology, 7491 Trondheim, Norway. Electronic address: kjell.m.varum@ntnu.no.
authors.forename: Kjell M
authors.initials: KM
authors.lastname: Vårum
keywords: Alginate; Chitosan oligomers; Crosslinkers; Gel characterization; Rheology