Microbial and algal alginate gelation characterized by magnetic resonance.
Advanced magnetic resonance (MR) relaxation and diffusion correlation measurements and imaging provide a means to non-invasively monitor gelation for biotechnology applications. In this study, MR is used to characterize physical gelation of three alginates with distinct chemical structures; an algal alginate, which is not O-acetylated but contains poly guluronate (G) blocks, bacterial alginate from Pseudomonas aeruginosa, which does not have poly-G blocks, but is O-acetylated at the C2 and/or C3 of the mannuronate residues, and alginate from a P. aeruginosa mutant that lacks O-acetyl groups. The MR data indicate that diffusion-reaction front gelation with Ca(2+) ions generates gels of different bulk homogeneities dependent on the alginate structure. Shorter spin-spin T(2) magnetic relaxation times in the alginate gels that lack O-acetyl groups indicate stronger molecular interaction between the water and biopolymer. The data characterize gel differences over a hierarchy of scales from molecular to system size.
Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT 59717-3920, USA.
Hilary T
HT
Fabich
Sarah J
SJ
Vogt
Matthew L
ML
Sherick
Joseph D
JD
Seymour
Jennifer R
JR
Brown
Michael J
MJ
Franklin
Sarah L
SL
Codd
D000464:Alginates / Q000737:chemistry*; D001704:Biopolymers / Q000737:chemistry; D004058:Diffusion; D005782:Gels / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D011550:Pseudomonas aeruginosa / Q000737:chemistry*
D000464:Alginates; D001704:Biopolymers; D005782:Gels