双子表面活性剂丁烷-1,4-二基-双（烷基二甲基溴化铵）与DNA的相互作用。

Interaction of gemini surfactants butane-1,4-diyl-bis(alkyldimethylammonium bromide) with DNA.

作者信息

Uhríková Daniela, Zajac Igor, Dubnicková Martina, Pisárcik Martin, Funari Sérgio S, Rapp Gert, Balgavý Pavol

机构信息

Faculty of Pharmacy, Comenius University, Odbojárov 10, 832 32 Bratislava, Slovak Republic.

出版信息

Colloids Surf B Biointerfaces. 2005 Apr 25;42(1):59-68. doi: 10.1016/j.colsurfb.2005.02.002.

DOI:10.1016/j.colsurfb.2005.02.002

PMID:15784327

Abstract

The size and structure of aggregates formed by interaction of DNA with homologous series of cationic gemini surfactants butane-1,4-diyl-bis(alkyldimethylammonium bromide) (CnGS, n=10-16 is the number of alkyl carbons) were investigated using UV-vis turbidity, dynamic light scattering and small-angle synchrotron X-ray (SAX) diffraction. The detailed analysis of turbidity in the range of lambda=450-600 nm indicates an anomaly in the growth of CnGS+DNA aggregates with increasing concentration of CnGS, possibly involving changes of structure and size of aggregates. Using dynamic light scattering, changes of the effective diameter of CnGS+DNA (n=12 and 16) aggregates formed in the CnGS concentration range 0.002-0.140 mmol/l were observed. SAX diffractograms show the presence of long-range organization of CnGS+DNA (n=12, 13, 14 and 16) aggregates due to DNA interaction with CnGS above the critical micellar concentration. The CnGS+DNA (n=12, 13 and 14) aggregates at 25 degrees C are packed in a lattice of two-dimensional hexagonal symmetry. With increasing C14GS:DNA molar ratio the changes of the lattice parameter in the range of 4.80-5.27 nm are observed at 25 degrees C. The aggregates undergo structural changes induced by temperature in the range 60-95 degrees C, which are accompanied by changes of the diffraction patterns, namely in the region of reciprocal spacing s=0.15-0.30 nm(-1).

摘要

使用紫外可见分光光度法、动态光散射和小角同步加速器X射线（SAX）衍射，研究了DNA与同系阳离子双子表面活性剂丁烷-1,4-二基-双（烷基二甲基溴化铵）（CnGS，n = 10 - 16为烷基碳数）相互作用形成的聚集体的大小和结构。对450 - 600 nm波长范围内的浊度进行详细分析表明，随着CnGS浓度的增加，CnGS + DNA聚集体的生长出现异常，这可能涉及聚集体结构和大小的变化。使用动态光散射，观察到在0.002 - 0.140 mmol/L的CnGS浓度范围内形成的CnGS + DNA（n = 12和16）聚集体的有效直径的变化。SAX衍射图表明，在临界胶束浓度以上，由于DNA与CnGS相互作用，CnGS + DNA（n = 12、13、14和16）聚集体存在长程有序结构。25℃时，CnGS + DNA（n = 12、13和14）聚集体以二维六方对称晶格堆积。在25℃下，随着C14GS:DNA摩尔比的增加，观察到晶格参数在4.80 - 5.27 nm范围内变化。聚集体在60 - 95℃范围内经历温度诱导的结构变化，这伴随着衍射图谱的变化，即在倒易间距s = 0.15 - 0.30 nm⁻¹区域。