Bysell Helena, Hansson Per, Malmsten Martin
Department of Pharmacy, Uppsala University, P.O. Box 580, SE-751 23 Uppsala, Sweden.
J Colloid Interface Sci. 2008 Jul 1;323(1):60-9. doi: 10.1016/j.jcis.2008.03.003. Epub 2008 Mar 8.
The interaction between poly-L-lysine (pLys) and oppositely charged poly(acrylic acid) (pAA) microgels (Ø approximately 80-120 microm) was studied by micromanipulator-assisted light microscopy and confocal laser scanning microscopy. The aim of this study was to investigate effects of peptide size, pH, and salt concentration on binding, transport, and distribution of pLys in pAA microgel particles and thereby also to outline the details of the gel deswelling in response to pLys binding and incorporation. Both peptide distribution and gel deswelling kinetics were found to be strongly influenced by the pLys molecular weight, originating partly from limited entry of large peptides into the gel particle core. Also pH was shown to influence both deswelling and pLys incorporation kinetics, with a decreased deswelling rate observed with increasing pH. These effects are determined by a complex interplay between the pH-dependence of both pLys and the gel network, also influencing volume transitions of the latter. Finally, salt concentration was shown to have a significant effect on both gel deswelling rate and pLys transport, with an increased electrolyte concentration resulting in decreased deswelling rate but also in an increased peptide transport rate within the microgel particles.
通过微操纵器辅助光学显微镜和共聚焦激光扫描显微镜研究了聚-L-赖氨酸（pLys）与带相反电荷的聚丙烯酸（pAA）微凝胶（直径约80 - 120微米）之间的相互作用。本研究的目的是研究肽大小、pH值和盐浓度对pLys在pAA微凝胶颗粒中的结合、运输和分布的影响，从而也概述凝胶因pLys结合和掺入而发生溶胀减小的细节。发现肽分布和凝胶溶胀动力学都受到pLys分子量的强烈影响，部分原因是大肽进入凝胶颗粒核心的能力有限。pH值也显示出对溶胀减小和pLys掺入动力学都有影响，随着pH值升高，溶胀减小速率降低。这些影响是由pLys和凝胶网络的pH依赖性之间的复杂相互作用决定的，这也影响了后者的体积转变。最后，盐浓度显示出对凝胶溶胀速率和pLys运输都有显著影响，电解质浓度增加导致溶胀减小速率降低，但也导致微凝胶颗粒内肽运输速率增加。
