Ionic polysaccharides. III. Dilute solution properties of hyaluronic acid fractions

✍ Scribed by Robert L. Cleland; John L. Wang

• Publisher: Wiley (John Wiley & Sons)
• Year: 1970
• Tongue: English
• Weight: 629 KB
• Volume: 9
• Category: Article
• ISSN: 0006-3525
• DOI: 10.1002/bip.1970.360090706

✦ Synopsis

Molecular weights by osmometry (gn), light scattering (Mu), and sedimeiitatioiidiffusion (M,D) were determined for selected fractions and unfractionated samples of hyaluronic acid in the molecular weight range 3 X 10e1.7 X 106. For the determination of M,D from the sedimentation coefficient s, a calibration procedure based on the data of Laurent, Ryan, and Pietruszkiewicz gave the following relations in 0.2M NaCl: log (s-l)~ = 14.681 -0.413 log M,D and log DO = -3.828 -0.568 log M*D, where subscript zero refers to zero concentration and D is the diffusion coefficient. The average Mandelkern-Flory parameter p in 0.2M NaCl is 3.0 X 106. Data for the intrinsic viscosity [?I] may be fitted for J4 > 105 by [q] = KIMa, where K', a are in 0.2144 NaCl, 0.0228, 0.816; in 0.5M NaCI, 0.0318, 0.777; in 0.liM HC1, 0.0279, 0.763, respectively. Below i M = 105, [a] appears to fall below the values calculated, possibly due to non-Gaiissian behavior of short chains. The second virial coefficient Al in 0.5M NaCl approaches the ideal Dorinan value, decreasing slightly with increasing molecular weight. The friction parameter P is about 2054 smaller than that of uncharged polymers of similar dimensions. The flexible coiling nature of this polymer is confirmed.