Rolland-Sabaté Agnès, Mendez-Montealvo Maria Guadalupe, Colonna Paul, Planchot Véronique
UR1268 Biopolymères Interactions Assemblages, INRA, F-44300 Nantes, France.
Biomacromolecules. 2008 Jul;9(7):1719-30. doi: 10.1021/bm7013119. Epub 2008 Jun 12.
Synthetic amyloses, pullulans, phytoglycogen, rabbit liver glycogen, oyster glycogen, and dextrans were studied using high-performance size-exclusion chromatography combined with multiangle laser light scattering (MALLS) and online quasi-elastic light scattering (QELS), which provided the RH distributions up to 65 nm. Different structural parameters were extracted from entire molar mass distributions, including the slope of the log-log plot of R H(i) versus M(i)and the rho(i )= R(Gi)/R(Hi)ratio. This approach enabled to observe deviations from the De Gennes scaling law concept. Evidences that the power laws do not obey the general universality were furnished by the observation of strong deviations in the relation between radii and molar masses for the branched polysaccharides, a decrease of rho-parameter with molar mass toward values much lower than theoretically expected, and the fact that relation between rho-parameter and apparent segment density did not show the expected power law decrease with an exponent of 1/3. The universality of scaling behavior seems no longer to be realized if structural heterogeneity governs the system.
使用高效尺寸排阻色谱结合多角度激光光散射（MALLS）和在线准弹性光散射（QELS）研究了合成直链淀粉、支链淀粉、植物糖原、兔肝糖原、牡蛎糖原和葡聚糖，这些方法提供了高达65nm的流体力学半径（RH）分布。从整个摩尔质量分布中提取了不同的结构参数，包括RH(i)对M(i)的对数-对数图的斜率以及rho(i)=R(Gi)/R(Hi)比值。这种方法能够观察到与德热纳标度定律概念的偏差。对于支链多糖，半径与摩尔质量之间的关系存在强烈偏差，rho参数随摩尔质量降低至远低于理论预期的值，以及rho参数与表观链段密度之间的关系未显示出预期的指数为1/3的幂律下降，这些观察结果提供了幂律不遵循一般普遍性的证据。如果结构异质性控制该系统，标度行为的普遍性似乎不再成立。
