Translational and rotational diffusion of flexible PEG and rigid dendrimer probes in sodium caseinate dispersions and acid gels

S. Salami, C. Rondeau-Mouro, M. Barhoum, J.P.M. van Duynhoven, F. Mariette

Research output: Contribution to journalArticleAcademicpeer-review

10 Citations (Scopus)

Abstract

The dynamics of rigid dendrimer and flexible PEG probes in sodium caseinate dispersions and acid gels, including both translational diffusion and rotational diffusion, were studied by NMR. Above the onset of the close-packing limit (C ~ 10 g/100 g H2O), translational diffusion of the probe depended on its flexibility and on the fluctuations of the matrix chains. The PEG probe diffused more rapidly than the spherical dendrimer probe of corresponding hydrodynamic radius. The greater conformational flexibility of PEG facilitated its motion through the crowded casein matrix. Rotational diffusion was, however, substantially less hindered than the translational diffusion and depended on the local protein–probe friction which became high when the casein concentration increased. The coagulation of the matrix led to the formation of large voids, which resulted in an increase in the translational diffusion of the probes, whereas the rotational diffusion of the probes was retarded in the gel, which could be attributed to the immobilized environment surrounding the probe. Quantitative information from PFG-NMR and SEM micrographs have been combined for characterizing microstructural details in SC acid gels.
Original languageEnglish
Pages (from-to)959-965
JournalBiopolymers
Volume101
Issue number9
DOIs
Publication statusPublished - 2014

Keywords

  • glucono-delta-lactone
  • hydrodynamic transport-properties
  • nuclear-magnetic-resonance
  • polystyrene latex spheres
  • aqueous polymer-solutions
  • light-scattering
  • nmr
  • suspensions
  • gelation
  • microstructure

Fingerprint Dive into the research topics of 'Translational and rotational diffusion of flexible PEG and rigid dendrimer probes in sodium caseinate dispersions and acid gels'. Together they form a unique fingerprint.

Cite this