Modulation of vesicular properties by variation of shapes of bolaform counter ions in hybrid-ion paried surfactants
作者:Santanu Bhattacharya、Soma De
DOI:10.1039/cc9960001283
日期:——
Four new vesicle-forming bolaphile/amphiphile ion pairs are synthesized; the bolaphile shapes in such hybrid systems strongly control their vesicular properties.
合成了四种新的囊泡形成亲波拉/两亲离子对;这种混合系统中的亲水性形状强烈控制其囊泡特性。
Synthesis and Vesicle Formation from Hybrid Bolaphile/Amphiphile Ion-Pairs. Evidence of Membrane Property Modulation by Molecular Design
作者:Santanu Bhattacharya、Soma De、M. Subramanian
DOI:10.1021/jo980315l
日期:1998.10.1
Four new hybrid (bolaphile/amphiphile) ion-pairs were synthesized. Electron microscopy indicated that each of these forms bilayer membranes upon dispersion in aqueous media. Membrane properties have also been examined by differential scanning calorimetry, microcalorimetry, temperature-dependent fluorescence anisotropy measurements, and UV-vis spectroscopy. The T-m values for the vesicular 1, 2, 3, 4, and 5 were 38, 12, 85, 31.3, and 41.6 degrees C, respectively. Interestingly the T-m values for 1 and 3 were found to depend on their concentration. The entrapment of small solute and the release capability have also been examined to demonstrate that these bilayers form enclosed vesicles. X-ray diffraction of the cast films has been performed to understand the nature and the thickness of these membrane organizations. The membrane widths ranged from 33 to 47 Angstrom. Finally, the above observations have been analyzed in light of the results obtained from molecular modeling studies. Thus we have demonstrated that membrane properties can be modulated by simple structural changes at the amphiphile level. It was shown that by judicious incorporation of central, isomeric, disubstituted aromatic units as structural anchors into different bolaphiles, one can modulate the properties of the resulting vesicles.