Polyelectrolyte properties of a plant and animal polysaccharide

Abstract

The principal properties of polyelectrolytes in aqueous solution are reviewed; experimental data obtained about polysaccharides in our laboratory identify the main electrostatic interactions which occur between macromolecular chains, between ionic sites on isolated chains or between counterions and polyelectrolytes. Two examples are described. Hyaluronan, a linear alternated copolymer type with one anionic site per repeat unit, is very soluble in water, with a persistence length around 8 nm and a rheological behavior directly related to the molecular weight and polymer concentration in the presence of external monovalent electrolyte. The second example is that of pectin for which the influence of the charge density is studied. It exhibits an important ionic selectivity among divalent counterions in dilute solution with a dimer formation followed by aggregation and gelation.

Mesoscopic structure of pectin in solution

“…The screening from NaCl is required to prevent complexities that may stem from changes in chain dimensions due to intra‐ and inter‐ molecular electrostatic interactions . In the presence of 0.1 M NaCl it is anticipated that the scattering curves reflect the conformations of the chains without intermolecular electrostatic interactions and is a common practice in SAXS sample preparation of biological or synthetic polyelectrolytes . It should be mentioned that it is possible to observe broadening of the scattering intensity curves at concentrations greater than the critical concentration ( c *) of the biopolymers .…”

Biomimetic gels with chemical and physical interpenetrating networks

“…It is known that natural polysaccharides contain a small fraction of anionic (carboxyl) residues, which exist in the salt form . These residues dissociate in water and provide the negative electrical charge on polysaccharide chains.…”

“…To improve the biocompatibility of synthetic hydrogels, biomacromolecules such as collagen, fibrin, fibronectin or various polysaccharides can be introduced as the fillers of gel networks …”

Polyelectrolytes–protein complexes: a viable platform in the downstream processes of industrial enzymes at scaling up level

“…A wide variety of synthetic and natural PE have been used to precipitate proteins that result in non‐soluble complex formation . The non‐soluble complex can be easily separated by centrifugation or simple decantation.…”

“…49 A wide variety of synthetic and natural PE have been used to precipitate proteins that result in non-soluble complex formation. 41,50,51 The non-soluble complex can be easily separated by centrifugation or simple decantation. Precipitation as a product concentration step has several advantages, such as easy scale up, simple equipment and can be based on a large variety of alternatives.…”