SANS study of the interactions among DNA, a cationic surfactant, and polystyrene latex particles
SANS study of the interactions among DNA, a cationic surfactant, and polystyrene latex particles
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DOI：
10.1021/la047251w
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发表时间：
2005-04-12
期刊：
影响因子：
3.9
通讯作者：
Lindman, B
中科院分区：
文献类型：
--
作者：
Cárdenas, M;Dreiss, CA;Lindman, B
DNA的压实由阳离子表面活性剂无论是在散装和吸附在乳胶颗粒的表面上，其次是第一次由SANS。在本体中，在阳离子表面活性剂存在下的DNA螺旋的总体尺寸的减少在负-正电荷比远低于相分离区域时观察到，在负-正电荷比为18时。此外，大的表面活性剂聚集体似乎在DNA-表面活性剂复合物内形成。另一方面，DNA吸附到胶乳颗粒的表面上，形成厚层，如通过SANS数据与核-壳形状因子的拟合所证明的。在负-正电荷比为38的情况下向DNA包被的胶乳颗粒中添加阳离子表面活性剂引起颗粒层的尺寸略微减小，其中阳离子表面活性剂均匀地分布在吸附层内。进一步减少的负-正电荷比为18诱导的SANS数据的显着变化，这表明吸附层的显着压实和形成的大的表面活性剂聚集体，类似于在散装检测。
The compaction of DNA by a cationic surfactant both in the bulk and adsorbed on the surface of latex particles was followed for the first time by SANS. In the bulk, a decrease in the overall size of the DNA coil in the presence of the cationic surfactant was observed at a negative-to-positive charge ratio far below the phase separation region, at a negative-to-positive charge ratio of 18. Additionally, large surfactant aggregates seem to form within the DNA-surfactant complex. On the other hand, DNA adsorbs onto the surface of latex particles, forming a thick layer, as evidenced by the fitting of the SANS data to a core-shell form factor. Addition of a cationic surfactant to the DNA-coated latex particles at a negative-to-positive charge ratio of 38 induces a slight decrease in the size of the particle layer, where the cationic surfactant is evenly distributed within the adsorbed layer. A further decrease of the negative-to-positive charge ratio to 18 induces a dramatic change in the SANS data that suggests significant compaction of the adsorbed layer and the formation of large surfactant aggregates, similar to those detected in the bulk.