Phase Separation in Mixed Carrageenan Systems

Lundin, Leif; Odic, K.; Foster, Tim; Norton, Ian T.

doi:10.1142/9781848160163_0027

Cited by 6 publications

(5 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Hence, the complexes between PGEs and APS might be simple. In addition, carrageenan tends to form a colloidal system with network structures in saline solutions (Langendorff et al, 2000;Guo et al, 2009;Lundin et al, 2000), which could result in the complicated adsorption process. The adsorption of PGEs on APS did not reach equilibrium within 48 h and this could be related to the change of the colloidal structure formed by APS (Fig.…”

Section: Adsorption Behaviors Of Pges On Mocs In Uvswmentioning

confidence: 99%

Adsorption kinetics of platinum group elements onto macromolecular organic matter in seawater

Gao

Xing

et al. 2019

Acta Oceanol. Sin.

View full text Add to dashboard Cite

Adsorption kinetics of the interaction between Pt, Pd and Rh (defined here as platinum group elements, PGEs) ions and macromolecular organic compounds (MOCs, >10 kDa), including humic acid, carrageenan and bovine serum albumin, and different cutoff fractions of natural organic matter (>1 kDa and >3 kDa) obtained from seawater using centrifugal ultrafiltration devices were investigated. For a given element, all the adsorption kinetics did not reach equilibrium except the interaction between Pt and >1 kDa cutoff, and between Pd and humic acid. For all the tested MOCs, the adsorption kinetics could be divided into two stages, a rapid adsorption process in the first 8 h and the desorption stage after the first 8 h until the equilibrium. The change trend of partition coefficient (log 10 K d ) values with experiment time was consistent with that of the kinetic curves. However, in the interaction between PGE ions and natural dissolved organic matter (NDOM), an obvious difference in the change trends of log 10 K d and kinetic curves was observed. It indicated that the partition behavior of PGE ions interacting with NDOM in seawater was a combined effect of different organic constituents. The adsorption and log 10 K d of PGEs in the >1 kDa NDOM fraction were higher and more stable than those in the >3 kDa NDOM fraction. The results also indicated that the 1-3 kDa NDOM may dominate the interaction between PGEs ions and NDOM. Moreover, no kinetic model could perfectly simulate the adsorption process. It indicated that the colloidal struction and morphology of MOCs or NDOM in seawater might be inhomogeneous. Hence, the interaction between PGE ions and organic matter in seawater was a complicated process and needs further research.

show abstract

Section: Adsorption Behaviors Of Pges On Mocs In Uvswmentioning

confidence: 99%

Adsorption kinetics of platinum group elements onto macromolecular organic matter in seawater

Gao

Xing

et al. 2019

Acta Oceanol. Sin.

View full text Add to dashboard Cite

show abstract

“…All the systems studied were intrinsically immiscible at temperatures well above the ordering temperature of gelatin, so that in this case it is difficult to draw any conclusions about the effect of ordering on the onset of demixing. It has however been suggested that mixtures of κ- and ι-carrageenan phase separate as a direct consequence of the ordering process of either of the polysaccharides . Other previous studies of the phase behavior of the gelatin/maltodextrin systems have focused on the effect of different thermal treatments and gelatin types on the morphology of the final system, on the incompatibility at temperatures well above the gelatin ordering temperature, and on the occurrence of phase inversion …”

Section: Introductionmentioning

confidence: 99%

Phase Separation Induced by Conformational Ordering of Gelatin in Gelatin/Maltodextrin Mixtures

et al. 2000

Self Cite

View full text Add to dashboard Cite

Mixtures of gelatin and maltodextrin in aqueous solution have been quenched to temperatures at which they are initially miscible but where gelatin ordering is initiated. In many cases phase separation was observed to occur after a significant time delay, and the dependence of these delays on quench temperature and biopolymer concentration has been studied in detail using turbidity measurements and confocal laser scanning microscopy (CLSM). Furthermore, by observing the optical rotation (OR) and turbidity of the system simultaneously, the gelatin helix content and the time delay before the onset of phase separation were monitored concurrently. The observed delay times were found to correspond to the time taken for the development of a certain degree of gelatin ordering, which drives the separation process. A further consequence of gelatin ordering is the viscosifying of the solution and, at sufficient concentrations, the formation of a gel. Therefore, rheological measurements have been used in addition to turbidity measurements and CLSM in order to monitor further the structural development of the systems. A comparison of the data obtained from these techniques shows that while the development of a certain elasticity will trap the system morphology, this elasticity is not directly related to that found at the gel point. At low maltodextrin concentrations, where phase separation was not detected by turbidity, transmission electron microscopy (TEM) has been used to examine the microstructure on a smaller length scale.

show abstract

“…The IC aggregates may contribute to the strain-stiffening response of the mixed KCIC gels, while the stiff and rigid KC aggregates are responsible for the breakup of the network in the LAOS measurement. Moreover, heterogeneity/phase-separated structure in the mixtures is suggested by other measurements in a larger length scale not accessible in this study. ,,,,, Therefore, the proposed network structure of mixed KCIC gels is schematically drawn in Figure .…”

Section: Results and Discussionmentioning

confidence: 74%

“…Moreover, heterogeneity/phase-separated structure in the mixtures is suggested by other measurements in a larger length scale not accessible in this study. 34,35,51,54,61,62 Therefore, the proposed network structure of mixed KCIC gels is schematically drawn in Figure 10.…”

Section: Temperature Dependence Of 1 H T 2 Of Carrageenan Gels On Coo...mentioning

confidence: 99%

Elaborating Spatiotemporal Hierarchical Structure of Carrageenan Gels and Their Mixtures during Sol–Gel Transition

Geonzon,

Hashimoto,

Oda

et al. 2023

Macromolecules

View full text Add to dashboard Cite

The control of the rheological properties of carrageenan gels from hierarchical structure design is very important for food and biotechnological applications. In this study, the viscoelastic properties from linear to nonlinear regimes and temperature-dependent spatiotemporal hierarchical structure of κ-(KC), ι-(IC) carrageenan gels, and their mixtures (KCIC) were investigated using dynamic rheology, small-angle neutron scattering (SANS), dynamic light scattering (DLS), and pulsed nuclear magnetic resonance (NMR). The nonlinear viscoelastic measurement revealed the characteristic signature of the KC and IC gels under large-amplitude oscillatory shear (LAOS), where IC showed a characteristic strain-stiffening and broke at large strain amplitude, while KC did not show a strain-stiffening and broke at small strain amplitude. The difference in the LAOS response was corroborated by the difference in the spatial and temporal hierarchical structures of the gels. The characteristic cross-sectional size of the aggregates, R g, of carrageenan gels measured by SANS confirmed that KC formed large bundles of rigid aggregates due to the extensive aggregation of KC during gelation. Furthermore, the temporal dynamics of the aggregates were resolved by pulsed NMR, demonstrating that IC gels formed loose aggregates in contrast to highly packed KC aggregates. Meanwhile, DLS revealed that KC formed a completely frozen network structure. Therefore, based on the collective understanding of carrageenan gels’ spatiotemporal hierarchical network structure, we demonstrate that the LAOS response of the carrageenan gels corresponds to the size of the aggregates and the dynamics of the network.

show abstract

Phase Separation in Mixed Carrageenan Systems

Cited by 6 publications

References 1 publication

Adsorption kinetics of platinum group elements onto macromolecular organic matter in seawater

Adsorption kinetics of platinum group elements onto macromolecular organic matter in seawater

Phase Separation Induced by Conformational Ordering of Gelatin in Gelatin/Maltodextrin Mixtures

Elaborating Spatiotemporal Hierarchical Structure of Carrageenan Gels and Their Mixtures during Sol–Gel Transition

Contact Info

Product

Resources

About