Lounis Feriel Meriem, Chamieh Joseph, Leclercq Laurent, Gonzalez Philippe, Cottet Hervé
Institut des Biomolécules Max Mousseron, IBMM, UMR 5247 CNRS, Université de Montpellier, Ecole Nationale Supérieure de Chimie de Montpellier, Place Eugène Bataillon, CC 1706, 34095 Montpellier CEDEX 5, France.
Polymers (Basel). 2017 Feb 4;9(2):50. doi: 10.3390/polym9020050.
The interactions between model polyanions and polycations have been studied using frontal continuous capillary electrophoresis (FACCE) which allows the determination of binding stoichiometry and binding constant of the formed polyelectrolyte complex (PEC). In this work, the effect of the poly(l-lysine) (PLL) molar mass on the interaction with statistical copolymers of acrylamide and 2-acrylamido-2-methyl-1-propanesulfonate (PAMAMPS) has been systematically investigated for different PAMAMPS chemical charge densities (15% and 100%) and different ionic strengths. The study of the ionic strength dependence of the binding constant allowed the determination of the total number of released counter-ions during the formation of the PEC, which can be compared to the total number of counter-ions initially condensed on the individual polyelectrolyte partners before the association. Interestingly, this fraction of released counter-ions, which was strongly dependent on the PLL molar mass, was almost independent of the PAMAMPS charge density. These findings are useful to predict the binding constant according to the molar mass and charge density of the polyelectrolyte partners.
已使用前沿连续毛细管电泳（FACCE）研究了模型聚阴离子与聚阳离子之间的相互作用，该方法可测定形成的聚电解质复合物（PEC）的结合化学计量和结合常数。在这项工作中，针对不同的PAMAMPS化学电荷密度（15%和100%）以及不同的离子强度，系统研究了聚（L-赖氨酸）（PLL）摩尔质量对其与丙烯酰胺和2-丙烯酰胺基-2-甲基-1-丙烷磺酸盐统计共聚物（PAMAMPS）相互作用的影响。对结合常数的离子强度依赖性研究使得能够确定PEC形成过程中释放的抗衡离子总数，该总数可与缔合前最初凝聚在各个聚电解质伙伴上的抗衡离子总数进行比较。有趣的是，这部分释放的抗衡离子强烈依赖于PLL摩尔质量，几乎与PAMAMPS电荷密度无关。这些发现有助于根据聚电解质伙伴的摩尔质量和电荷密度预测结合常数。
