title: Synthesis and physicochemical characterization of a novel ampholytic pullulan derivative with amphiphilic behavior in alkaline media.
abstract: Pullulan derivative was synthesized by coupling carboxymethylpullulan (degree of substitution DS(0)(in)=0.7) and dimethylaminopropylamine (DMAPA), activated by a hydrosoluble carbodiimide N(')-(3-dimethylaminopropyl)-N-ethylcarbodiimide hydrochloride (EDAC). FTIR and (13)C and (1)H NMR spectroscopic analyses have evidenced that the polysaccharide has been successfully modified. (1)H NMR, nitrogen analysis, and conductimetric measurements allow determination of the degree of substitution in both carboxylic acid and amine functions. We have found that both functions present a similar DS of 0.35, which is characteristic of an ampholytic polymer with possible zwitterionic-type properties. Solution properties have been studied by flow field flow fractionation (F4) coupled on-line with multiangle laser light scattering (MALLS) and quasi elastic light scattering (QELS), surface tension, and viscosity measurements. The behavior has been found largely pH dependent and an amphiphilic behavior has been evidenced in alkaline media.
authors.affiliation: UMR 6522 CNRS, Université de Rouen, Mont Saint Aignan 76821 Cedex, France.
authors.forename: Z
authors.initials: Z
authors.lastname: Souguir
authors.forename: S
authors.initials: S
authors.lastname: Roudesli
authors.forename: E
authors.initials: E
authors.lastname: About-Jaudet
authors.forename: D
authors.initials: D
authors.lastname: Le Cerf
authors.forename: L
authors.initials: L
authors.lastname: Picton
mesh_terms: D005936:Glucans / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007525:Isoelectric Focusing / Q000379:methods; D007526:Isoelectric Point; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008956:Models, Chemical; D011108:Polymers / Q000737:chemistry; D011134:Polysaccharides / Q000737:chemistry*; D011437:Propylamines / Q000737:chemistry*; D013053:Spectrophotometry; D013055:Spectrophotometry, Infrared; D013499:Surface Properties; D013696:Temperature
chemical_list: D005936:Glucans; D011108:Polymers; D011134:Polysaccharides; D011437:Propylamines; C009109:pullulan