title: Size, structure and scaling relationships in glycogen from various sources investigated with asymmetrical flow field-flow fractionation and 1H NMR.
abstract: In this paper we investigate the size, structure and scaling relationships in glycogen isolated from five different animal sources. For this purpose a versatile fractionation technique, asymmetrical flow field-flow fractionation (AsFlFFF), coupled to multi-angle light scattering, is utilized. For determination of the average degree of branching (1)H NMR is utilized. The results give a detailed insight into the physico-chemical properties of glycogen over the whole size distribution. The results show that glycogen is a hyper branched macromolecule with wide size distributions, and in some samples two major populations are clearly observed which most likely correspond to β- and α-particles of glycogen. The results also illustrates that glycogen is a polysaccharide showing rather diverse conformational properties, over the size distribution, depending on its origin and the extraction procedure. The ratio between root-mean-square radius and hydrodynamic radius varies depending of both sample origin the molar mass of the macromolecules, reflecting differences in conformation and scaling within the size distribution. Thus, a priori assumptions regarding the r(rms)/r(h) are difficult to make and r(rms)/r(h) based on average properties give an incomplete description of the properties. Furthermore, the results display the strength of the apparent density (as obtained from AsFlFFF-MALS-RI) as a characterization parameter for scaling in disperse macromolecules.
authors.affiliation: Department of Experimental Medical Science, Lund University, Lund, Sweden. celine.fernandez@med.lu.se
authors.forename: Céline
authors.initials: C
authors.lastname: Fernandez
authors.forename: Cinthia Carola
authors.initials: CC
authors.lastname: Rojas
authors.forename: Lars
authors.initials: L
authors.lastname: Nilsson
mesh_terms: D000818:Animals; D031521:Fractionation, Field Flow / Q000379:methods*; D006003:Glycogen / Q000737:chemistry*; D001467:Hordeum / Q000737:chemistry; D008027:Light; D009682:Magnetic Resonance Spectroscopy; D008970:Molecular Weight; D011522:Protons; D012542:Scattering, Radiation; D013213:Starch / Q000737:chemistry; D013997:Time Factors
chemical_list: D011522:Protons; D013213:Starch; D006003:Glycogen