Control and detection of molecular dynamics in the diluted magnetic fluid solution under magnetic field.

磁场下稀释磁性流体溶液中分子动力学的控制与检测。

基本信息

批准号：
08454236
负责人：
FUJIWARA Kitao
金额：
$ 5.06万
依托单位：
HIROSHIMA UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1996
资助国家：
日本
起止时间：
1996 至 1997
项目状态：
已结题

项目摘要

Magnetic fluid is a colloid solution of the ferromagnetic fine particles which can be dispersed in the liquid (water or organic solvents) by covering their surfaces with surfactants. Diameter of the colloid of magnetic fluid is about 10 nm. When the single layr of the surfactant covers the particle, magnetic fluid is hydrophobic and dispersed in non-aqueous solvents. When the double layrs of the surfactant cover the particle, magnetic fluid is hydrophilic and soluble in water. In this study, the magnetic fluid was diluted with the solvent which contains the fluorescent dye. We assumed that the magnetic fluid particles produce clusters under the magnetic field. When the interaction between the dye and the magnetic fluid particle is strong, the fluorescent dye molecules are associated to the cluster. In this case, it provides a variation in the polarized fluorescence intensity of the dye by excitation of the light source polarized with parallel against the magnetic field. When water solube magnetic fluid (the first layr of surfactant : linoleic acid, the second layr of surfactant : polyethylene glycol lauryl ether) was used, the fluorescence intensity of Rhodamine dyes increased by over 200%, but other dye did not. Also, variations in the fluorescence in the intensities of anthracene derivatives under a magnetic field were investigated in the presence of a diluted magnetic fluid (first layr of the surfactant : oleic acid). In this case, the intensity of the fluorescence decreased by about 10%. Although the fluorescence intentisities of most of the anthracene derivatives showed a similar decrease in magnitude, that of 9,10-dimethylanthracene showed a large decrease. On the other hand, fluorescence increased when excitation and fluorescence were perpendicular to the magnetic field. These results show the possibility of the separation of the dye molecules due to the affinity specific to the dye and the surfactant used in the magnetic fluid y means of the present method.

磁流体是铁磁性微粒的胶体溶液，通过用表面活性剂覆盖其表面而分散在液体（水或有机溶剂）中。磁性流体胶体的直径约为10纳米。当单层表面活性剂覆盖颗粒时，磁流体具有疏水性并分散在非水溶剂中。当表面活性剂双层覆盖颗粒时，磁流体具有亲水性并可溶于水。在这项研究中，磁性流体用含有荧光染料的溶剂稀释。我们假设磁性流体颗粒在磁场下产生团簇。当染料和磁性流体颗粒之间的相互作用较强时，荧光染料分子与簇结合。在这种情况下，它通过激发与磁场平行偏振的光源来提供染料的偏振荧光强度的变化。当使用水溶性磁流体（第一层表面活性剂：亚油酸，第二层表面活性剂：聚乙二醇月桂基醚）时，罗丹明染料的荧光强度增加了200%以上，而其他染料则没有。此外，在稀释的磁性流体（表面活性剂的第一层：油酸）存在下研究了磁场下蒽衍生物的荧光强度的变化。在这种情况下，荧光强度降低了约10%。尽管大多数蒽衍生物的荧光强度均表现出类似的下降幅度，但9,10-二甲基蒽的荧光强度却表现出较大的下降。另一方面，当激发和荧光垂直于磁场时，荧光增加。这些结果表明，由于本方法的磁流体中使用的染料和表面活性剂的特异性亲和力，染料分子分离的可能性。