Instituto de Física, Universidade de São Paulo, São Paulo, Brazil.
Langmuir. 2013 Sep 3;29(35):11102-8. doi: 10.1021/la4016004. Epub 2013 Aug 20.
In this work, we investigate the effect of a small single-stranded oligonucleotide (ODN) on the colloid stability and structure of cationic diC14-amidine liposomes. Dynamic light scattering (DLS) shows that small, stable, anionic assemblies are formed in presence of excess ODN negative charge. This charge overcompensation condition was further characterized. A less cooperative bilayer phase transition is observed by differential scanning calorimetry (DSC). Electron spin resonance (ESR) spectra of probes at different bilayer depths show that ODN electrostatic adsorption increases the rigidity of both interdigitated gel and lamellar fluid phases. The increase in gel phase rigidity could be explained by the transformation of an adjacent to an interpenetrated interdigitation. Interdigitated fusogenic bilayers may find interesting applications in delivery of therapeutic oligonucleotides.
在这项工作中，我们研究了一小段单链寡核苷酸（ODN）对阳离子二 C14-脒脂质体胶体稳定性和结构的影响。动态光散射（DLS）表明，在过量 ODN 负电荷存在的情况下，形成了小的、稳定的阴离子组装体。进一步对这种电荷超补偿条件进行了表征。差示扫描量热法（DSC）观察到的双层相转变不那么协同。位于不同双层深度的探针的电子自旋共振（ESR）谱表明，ODN 静电吸附增加了互穿交错凝胶相和层状流体相的刚性。凝胶相刚性的增加可以通过相邻的互穿交错的转变来解释。交错融合的融合双层可能在递送治疗性寡核苷酸方面有有趣的应用。
